Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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L-2452R
Title: LUBRICATING OIL COMPOSITIONS AND CONCENTRATES
Field of the Invention
This invention relates to lubricating oil compo-
sitions. In particular, this invention relates to lubri-
cating oil compositions exhibiting improved oxidation
and wear performance.
Backqround of the Invention
Lubricating oils which are utilized in internal
combustion engines, and in particular, in spark-ignited
and diesel engines are constantly being modified and
improved to provide improved performance. Various organ-
izations including the SAE (Society of Automotive Engi-
neers), the ASTM tformerlY the American Society for
Testing and Materials) and the ~PI (American Petroleum
Institute) as well as the automotive manufacturers
continually seek to improve the performance of lubricat-
i~g oils. Various standards have been established and
modified over the years through the efforts of these
organizations. As engines have increased in power
output and complexity, the performance requirements have
been increased to provide lubricating oils that will
exhibit a reduced tendency to deteriorate under condi-
tions of use and thereby to reduce wear and the forma-
tion of such undesirable deposits as varnish, sludge,
carbonaceous materials and resinous materials which tend
to adhere to the various engine parts and reduce the
efficiency of the engines.
Zr)~7~9
--2--
In general, different classifications of oils
and performance requirements have been established for
crankcase lubricants to be used in spark-ignited and
diesel engines because of the di~ferences in/and the
demands placed on, lubricating oils in these applica-
tions. Until recently, high quality commercially avail-
able quality oils designed for spark-ignition engines
were identified and labeled as "SF" oils. These oils
are capable of satisfying the performance requirements
o~ API Service Classification SF. A new API Service
Classification SG has now been established, and this oil
is to be la~eled "SG". The oils designated as SG must
pass the performance requirements of API Service Classi-
fication SG which have ~een esta~lished to insure that
these new oils will possess additional desirable proper-
ties and performance capabilities in excess o~ those
required for SF oils. The SG oils are designed to mini-
mize engine wear and deposits and also to minimize lubri-
cant thickening in service. The SG oils are intended to
improve engine performance and durability when compared
to all previous engine oils marketed for spark-ignition
engines. An added feature of SG oils is the inclusion
o~ the requirements of the ~PI Service Classification CC
category (diesel) into the SG specification.
In order to meet the per~ormance requirements
of S~ oils, the oils must successfully pass the follow-
ing gasoline and diesel engine tests which have been
established as standards in the industry: The Ford
Sequence VE Test; The Buick Sequence IIIE Test; The
Oldsmobile Sequence IID Test; The CRC L-38 Test; and The
Caterpillar Single Cylinder Test Engine 1H2. The Cater-
pillar Test is included in the performance requirements
in order to also qualify the oil for the light duty die-
--3--
sel use (diesel performance catetory "CC"). If it isdesired to have the SG classification oil also qualify
for heavy duty diesel use, (diesel category "CD") the
oil formulation must pass the more stringent performance
requirements of the Caterpillar Single Cylinder Test
Engine 1G2. The procedures and performance criteria for
all of these tests have been established by the indus-
try, and the tests are described in more detail below.
When it is desired that the lubricating oils of
the SG classification also exhibit improved fuel econ-
omy, the oil must meet the requirements of the Sequence
VI Fuel Efficient Engine Oil Dynamometer Test.
A new classification of diesel engine oil also
has been established through the joint efforts of the
SAE, ASTM and the API, and the new diesel oils will be
labeled "CE". The oils meeting the new diesel classifi-
cation CE will have to be capable of meeting additional
performance requirements not found in the present CD
category including the Mack T-6, Mack T-~, and the
Cummins NTC-400 Tests.
An ideal lubricant for most purposes should pos-
sess the same viscosity at all temperatures. Available
l~ubricants, however, depart from this ideal. Materials
which have been added to lubricants to minimize the vis-
cosity change with temperature are called viscosity-modi-
fiers, viscosity-improvers, viscosity-index-improvers or
VI improvers. In general, the materials which improve
the VI characteristics of lubricating oils are oil solu-
ble organic polymers, and these polymers include polyiso-
butylenes, polymethacrylates ~i.e., copolymers of vari-
ous chain length alkyl methacrylates); copolymers of
ethylene and propylene; hydrogenated block copolymers of
styrene and isoprene; and polyacrylates (i.e., copoly-
mers of various chain length alkyl acrylates).
Y8~
--4--
Other materials have been included in the lubri-
cating oil compositions to enable the oil compositions
to meet the various performance requirements, and these
include dispersants, detergents, friction modifiers,
corrosion-inhibitors, etc. Dispersants are employed in
lubricants to maintain impurities in suspension, parti-
cularly those formed during operation of an internal
combustion engine, rather than allowing them to deposit
as sludge. Materials have been described in the prior
art which exhibit both viscosity-improving and disper-
sant properties. One type of compound having both
properties is comprised of a polymer backbone onto which
backbone has been attached one or more monomers having
polar groups. Such compounds are frequently prepared by
a grafting operation wherein the backbone polymer is
reacted directly with a suitable monomer.
Dispersant additives for lubricants comprising
the reaction products of hydroxy compounds or amines
with substituted succinic acids or their derivatives
~lso have been described in the prior art, and typical
dispersants of this type are disclosed in, for example,
U.S. Patents 3,272,746; 3,522,179; 3,219,666; and
4i,234,435. When incorporated into lubricating oils, the
compositions described in the '435 patent function as
dispersants/detergents and viscosity-index improvers.
Lubricating oil compositions containing oil-sol-
uble transition metal-containin~ compounds also have
been described in the prior art. The transition metal
compounds often are salts of acidic materials such as
carboxylic acids, sulfonic acids, or mixtures thereof.
For example, U.S. Patent 4,162,986 (Al~aitis et al~
describes transition metal salts of mixed organic carbox-
ylic and sulfonic or second carboxylic acids and their
Z~ 78~3
use as lubricant additives. The transition metal com-
pounds are also suggested as being useful as catalysts,
anti-knock agents, combustion improvers, smoke suppres-
sants, curing agents, driers, micronutrient sources,
etc. Hydrolyzable manganese soaps which are stabilized
by the inclusion of propionic acid are described as
useful in greases, lubricating oils, fuels, etc. in U.S.
Patent 3,762,890 (Collins).
Other patents and publications suggesting the
use of various manganese salts and compounds as addi-
tives in lubricating oil compositions include, for
example, U.S. Patents 2,364,283 (Freuler); 2,378,820
(Amott); 2,389,527 (McCleary); 3,346,493 (LeSuer);
3,827,979 (Piotrowski et al); 4,252,659 (Ali); 4,505,718
(Dorer); 4,633,001 (Cells); 4,664,677 (Dorer et al);
European Patent Application 0271363; and European Patent
Application 0,290,457. U.S. Patent 3,941,606 (Collins
et al) describes hydrocarbon-soluble compositions com-
prising the reaction product of a polyvalent metal
(e.g., Mn, Co and Ni) or polyvalent metal derivative
(e.g., MnO, CoO and NiO) with a mixture comprising at
least one acidic compound (e.g., fatty acids) and at
least one polyhydroxy compound. The compositions are
described as useful as siccatives in paint and similar
coating drier compositions, fuel additives, and stabil-
izers for plastics.
U.S. Patent 4,505,718 and EP 0,290,~57 describe
hydrocarbon-soluble compositions which comprise one or
more transition metal salts of at least one organic
carboxylic acid, and at least one hydrocarbon-soluble
ashless dispersant. The transition metal salts describ-
ed in these patents include manganese salts of organic
acids including carboxylic acids, sulfonic acids and
;~C)3L7819
--6--
phosphorus acids. A preference is expressed for over-
based transition metal salts including manganese salts
of the organic acids. Overbased metal salts are defined
in the art and herein as salts in which the metal is
present in excess of the stoichiometric amount required
to react with the acidic groups of the organic acids. A
larger number of ashless dispersants are disclosed as
being useful in combination with the transition metal
salts. References are included to many patents and
several textbook publications describing ashless dispers-
ants. Acylated nitrogen-containing dispersants are
included in the types of dispersants utilized in the
lubricant compositions. U.S. Patent 4,505,718 describes
lubricating oil compositions containing from 1 to about
500 ppm of the transition metal (as metal) and about 5
to about 1000 ppm by weight of ashless dispersant.
U.S. Patent 4,664,677 describes compositions
comprising a mixture of manganese salts and copper
salts. The compositions are described as being useful
in fuel compositions.~ Fuels containing the copper and
manganese compositions are disclosed as being useful for
reducing the ignition temperature of exhaust particulate
~rom diesel engines when operated using the described
fuel compositions.
European ~atent Publication 271363 describes
oil-soluble compositions which contain a dispersant
material, a detergent material, a zinc dihydrocarbyl
dithiophosphate anti-wear material, and a compatibiliz-
ing material which comprises a metal salt o~ a hydrocar-
byl-substituted mono- or dicarboxylic acid. A number of
dispersants are described including those based on long
chain hydrocarbyl-substituted mono- or dicarboxylic acid
materials such as long chain hydrocarbons, generally
polyolefin-substituted with an alpha- or beta-unsaturat-
ed dicarboxylic acid. The dispersants generally contain
at least about 1.05 moles (e.g., 1.05 to 1.2 moles, or
higher) of the acid per mole of polyolefin. The olefin
polymers usually have a number average molecular weight
of above 700 including number average molecular weights
within the range of rom 1500 to 5000. Polyisobutylene
is described as an especially suitable starting mater-
ial. The dispersants are obtained by reacting the dicar-
boxylic acid materials with amines, alcohols, amino
alcohols, etc. The metal salts suitable as compatibil-
izing materials include salts of metals from Groups Ib,
IIb, IIIb, IVb, Vb, VIb, VIIb and VIII of the Periodic
Table. Preferred metals are from Groups Ib and IIb, and
the most preferred metal is copper. The salts may be
basic, neutral or acidic, and they may be formed by
reacting the reactive metal compound with any of the
materials described as being dispersant materials which
have at least one free carboxylic acid group. Specific
examples of compatibilizing materials include the copper
and zinc salts of polyisobutenyl succinic anhydride.
SummarY of the Invent1on
~ ~ lubricating oil composition is described
which is useful in internal combustion engines and which
exhibit impro~ed oxidation and wear performance~ More
particularly, lubricating oil compositions are described
which comprise
(A) a major amount of oil of lubricating vis-
cosity;
(B) at least about 1.0% by weight of at least
one carboxylic derivative composition produced by react-
ing
--8--
(B-1 ) at least one substituted succinic
acylating agent with
(B-2) at least one amine compound character-
ized by the presence within its structure of at least
one HN< group wherein said substituted succinic acylat-
ing a~ents consist of substituent ~roups and succinic
groups wherein the substituent groups are derived from
polyalkene, said polyalkene being characterized by an Mn
value of 1300 to about 5000 and an Mw/Mn value of about
1.5 to about 4.5, said acylating agents being character-
ized by the presence within their structure of an aver-
age of at least 1.3 succinic groups for each equivalent
weight o~` substituent groups; and
(C) at least one manganese compound in an
amount sufficient to provide from 1 to about 500 ppm of
manganese as metal, provided that the manganese compound
is not a neutral manganese dihydrocarbyl phosphorodi-
thioate.
The oil compositions also may contain other desirable
additives including
(D) at least one metal dihydrocarbyl phosphoro-
dithioate;
~ (E) detergent effective amounts of at least
one neutral or basic alkali metal salt of a sulfonic or
carboxylic acid; and/or
(F) at least one carboxylic ester derivative
is defined herein.
In one embodiment, the oil compositions of the present
invention contain the above additives and other addi-
tives described in the specification in an amount suffi-
cient to enable the oil to meet all the performance
requirements of the API Service Classification identi-
fied as "SG".
78~9
Detailed Description of the Invention
Throughout this specification and claims, refer-
ences to percentages by weight of the various compo--
nents, except for component (A) which is oil, are on a
chemical basis unless otherwise indicated. For example,
when the oil compositions of the invention are described
as containing at least 2% by weight of (B), the oil
composition comprises at least 2% by weight of (s) on a
chemical basis. Thus, if component (B) is available as
a 50% by weight oil solution, at least 4% by weight of
the oil solution would be included in the oil composi-
tion.
The number of equivalents of the acylating a-
gent depends on the total number of carboxylic functions
present. In determining the number of equivalents for
the acylating agents, those carboxyl functions which are
not capable of reacting as a carboxylic acid acylating
agent are excluded. In general, however, there is one
equivalent of acylating agent for each carboxy group in
these acylating agents. For example, there are two
equivalents in an anhydride derived from the reaction of
one mole of olefin polymer and one mole of maleic anhy-
dride. Conventional techniques are readily available for
determining the number of carboxyl functions (e.g., acid
number, saponification number) and, thus, the number of
equivalents of the acylating agent can be readily deter-
mined by one skilled in the art.
An equivalent weight of an amine or a polyamine
is the molecular weight of the amine or polyamine divid-
ed by the total number of nitrogens present in the mole-
cule. Thus, ethylene diamine has an equivalent weight
equal to one-half of its molecular weight; diethylene
triamine has an equivalent weight equal to one-third its
7~
--1 o--
molecular weight. The equivalent weight of a commer-
cially available mixture of polyalkylene polyamine can
be determined by dividing the atomic weight of nitrogen
(14) by the %N contained in the polyamine and multiply-
ing by 100; thus, a polyamine mixture containing 34%
nitrogen would have an equivalent weight of 41.2. An
e~uivalent weight of ammonia or a monoamine is the
molecular weight.
An equivalent weight of a hydroxyl-substituted
amine to be reacted with the acylating agents to form
the carboxylic derivative (B) is its molecular weight
divided by the total number of nitrogen groups present
in the molecule. For the purpose of this inYention in
preparing component (B), the hydroxyl groups are ignored
when calculating equivalent weight. Thus, ethanolamine
would have an equivalent weight equal to its molecular
weight, and diethanolamine has an equivalent weight
(based on nitrogen) equal to its molecular weight.
The equivalent weight of a hydroxyl-substituted
amine used to form the carboxylic ester derivatives (F)
useful in this invention is its molecular weight divided
by the number of hydroxyl groups present, and the nitro-
gen atoms present are ignored. Thus, when preparing
esters from, e.g., diethanolamine, the equivalent weight
is one-half the molecular weight of diethanolamine.
The terms "substituent", "acylating agent" and
"substituted succinic acylating agent" are to be given
their nor~al meanings. For example, a substituent is an
atom or group of atoms that has replaced another atom or
group in a molecule as a result of a reaction. The
terms acylating agent or substituted succinic acylating
agent refer to the compound per se and does not include
unreacted reactants used to form the acylating agent or
substituted succinic acylating agent.
,
~r~17~
1 1 ,
(A) Oil of Lubricatinq_ViscositY.
The oil which is utilized in the preparation of
the lubricants of the invention may be based on natural
oils, synthetic oils, or mixtures thereof.
Natural oils include animal oils and vegetable
oils (e.g., castor oil, lard oil) as well as mineral
lubricating oils such as liquid petroleum oils and sol-
vent treated or acid treated mineral lubricating oils of
the paraffinic, naphthenic or mixed paraffinic-naphthen-
ic types. Oils of lubricating viscosity derived from
coal or shale are also useful. Synthetic lubricating
oils include hydrocarbon oils and halosubstituted hydro-
carbon oils such as polymerized and interpolymerized
olefins (e.g., polybutylenes, polypropylenes, propylene-
isobutylene copolymers, chlorinated polybutylenes,
etc.); poly~1-hexenes), poly(1-octenes), poly(1-dec-
enes), etc. and mixtures thereof; alkylbenzenes (e.g.,
dodecylbenzenes, tetradecylbenzenes, dinonylbenzenes,
di-(2-ethylhexyl)-benzenes, etc.); polyphenyls (e.g.,
biphenyls, terphenyls, alkylated polyphenyls, etc.);
alkylated diphenyl ethers and alkylated diphenyl sulf-
ides and the derivatives, analogs and homologs thereof
and the like.
Alkylene oxide polymers and interpolymers and
derivatives thereof where the terminal hydroxyl groups
have been modified by esterification, etherification,
etc., constitute another class of known synthetic lub-
ricating oils that can be used. These are exemplified
by the oils prepared through polymerization of ethylene
oxide or propylene oxide, the alkyl and aryl ethers of
these polyoxyalkylene polymers (e.g., methylpolyiso-
propylene glycol ether having an average molecular
weight of about 1000, diphenyl ether of polyethylene
7~3~9
glycol having a molecular weight of about 500-1000, di-
ethyl ether of polypropylene glycol having a molecular
weight of about 1000-1500, etc.) or mono- and polycar-
boxylic esters thereof, for example, the acetic acid
esters, mixed C3_8 fatty acid esters, or the Cl3 Oxo
acid diester of tetraethylene glycol.
Another suitable class of synthetic lubricating
oils that can be used comprises the esters of dicarbox-
ylic acids (e.g., phthalic acid, succinic acid, alkyl
succinic acids, alkenyl succinic acids, maleic acid,
azelaic acid, suberic acid, sebacic acid, fumaric acid,
adipic acid, linoleic acid dimer, malonic acid, alkyl
malonic acids, alkenyl malonic acids, etc.) with a var-
iety of alcohols (e.g., butyl alcohol, hexyl alcohol,
dodecyl alcohol, 2-ethylhexyl alcohol, ethylene glycol,
diethylene glycol monoether, propylene glycol, etc.)
Specific examples of these esters include dibutyl adi-
pate, di(2-ethylhexyl) sebacate, di-n-hexyl fumarate,
dioctyl sebacate, diisooctyl azelate, diisodecyl azel-
ate, dioctyl phthalate, didecyl phthalate, dieicosyl
sebacate, the 2-ethylhexyl diester of linoleic acid
dimer, the complex ester formed by reacting one mole of
sebacic acid with two moles of tetraethylene glycol and
two moles of 2-ethylhexanoic acid and the like.
Esters useful as synthetic oils also include
those made from C5 to C12 monocarboxylic acids and
polyols and polyol ethers such as neopentyl glycol, tri-
methylol propane, pentaerythritol, dipentaerythritol,
tripentaerythritol, etc.
Silicon-based oils such as the polyalkyl-, poly-
aryl-, polyalkoxy-, or polyaryloxy-siloxane oils and sil-
icate oils comprise another useful class of synthetic
lubricating oil (e.g., tetraethyl silicate, tetraisopro-
2f~7 ~ ~
pyl silicate, tetra-(2-ethylhexyl)silicate, tetra-(4-
methylhexyl)silicate, tetra-(p-tert-butylphenyl) sili-
cate, hexyl-t4-methyl-2-pentoxy)disiloxane, poly-
(methyl)siloxanes, poly(methylphenyl)siloxanes, etc.).
Other synthetic lubricating oils include liquid esters
of phosphorus-containing acids (e.g., tricresyl phos-
phate, trioctyl phosphate, diethyl ester of decane
phosphonic acid, etc.), polymeric tetrahydrofurans and
the like.
Unrefined, refined and rerefined oils, either
natural or synthetic (as well as mixtures of two or more
of any of these) of the type disclosed hereinabove can
be used in the concentrates of the present invention.
Unrefined oils are those obtained directly from a natur-
al or synthetic source without further purification
treatment. For example, a shale oil obtained directly
from retortin~ operations, a petroleum oil obtained
directly from primary distillation or ester oil obtained
directly from an esterification process and used without
further treatment would be an unrefined oil. Refined
oils are similar to the unrefined oils except they have
been further treated in one or more purification steps
to improve one or more properties. Many such purifica-
tion techniques are known to those skilled in the art
such as solvent extraction, hydrotreatin~, secondary dis-
tillation, acid or base ex~raction, filtration, percola-
tion, etc. Rerefined oils are obtained by processes
similar to those used to obtain refined oils applied to
refined oils which have been already used in service.
Such rerefined oils are also ~nown as reclaimed, recy-
cled or reprocessed oils and often are additionally
processed by techniques directed to removal of spent
additives and oil breakdown products.
~lr3~B~!~
-14-
(B) Carboxylic Derivatives.
Component (B) which is utilized in the lubricat-
ing oils of the present invention is at least one carbox-
ylic derivative composition produced by reacting tB-1)
at least one substituted succinic acylating agent with
(B-2) at least one amine compound containing at least
one HN< ~roup, and wherein said acylating agent consists
of substituent groups and succinic groups wherein the
substituent groups are derived from a polyalkene charac-
terized by an Mn value of about 1300 to about 5000 and
an Mw/Mn ratio of about 1.5 to about 4.5, said acylating
agents being characterized by the presence within their
structure of an average of at least about 1.3 succinic
groups for each equivalent weight of substituent groups.
Generally, the reaction involves from about 0.5 equiva-
lent to about 2 moles of the amine compound per equiva-
lent of acylating agent.
The carboxylic derivatives (B) are included in
the oil compositions to improve dispersancy and VI prop-
erties of the oil compositions. In qeneral from about
1% to about 10~ or 15% by weight of component (B) can be
included in the oil compositions, although the oil compo-
s~itions preferably will contain at least 2% and in some
instances 3~ or more by weight of component (B).
The substituted succinic acylating agent (B-1)
utilized the preparation of the carboxylic derivative
(B) can be characterized by the presence within its
structure of two groups or moieties. The first group or
moie~y is referred to hereinafter, for convenience, as
the "substituent group(s)" and is derived from a poly-
alkene. The polyalkene from which the substituted
groups are derived is characterized by an Mn (number
average molecular weight) value of from about 1300 to
-15-
about 5000, and an Mw/Mn value of at least about 1.5 and
more generally from about 1.5 to about 4.5 or about 1.5
to about 4Ø The abbreviation Mw is the conventional
symbol representing the weight average molecular weight.
Gel permeation chromatography (GPC) is a method which
provides measurements o~ molecular sizes from which both
weight average and number average molecular weights as
well as the entire molecular weight distribution of the
polymers may be determined. For purpose of this inven-
tion a series of fractionated polymers of isobutene,
polyisobutene, is used as the calibration standard in
the GPC.
The techniques for determining Mn and Mw values
of polymers are well known and are described in numerous
books and articles. For example, methods for the deter-
mination of Mn and molecular weight distribution of poly-
mers is described in W.W. Yan, J.J. Kirkland and D.D.
Bly, "Modern Size Exclusion Liquid Chromatographs", J.
Wiley & Sons, Inc., 1979.
The second group or moiety in the acylating
agent is referred to herein as the "succinic group(s)".
The succinic groups are those groups characterized by
t~he structure
X-C-C-C-~-X' (I~
wherein X and X' are the same or different provided at
least one of X and Xi is such that the substituted
succinic acylating agent can function as carboxylic
acylating agents. That is, at least one of X and X'
must be such that the substituted acylating agent can
form amides or amine salts with amino compounds, and
~ 7~3~ 9
otherwise function as a conventional carboxylic acid
acylating agents. ~ransesterification and transamida-
tion reactions are considered, for purposes of this
invention, as conventional acylating reactions.
Thus, X and/or X' is usually -OH, -O-hydrocar-
byl, -O-M~ where M+ represents one e~uivalent of a
metal, ammonium or amine cation, -NH2, -Cl, -Br, and
together, X and ~' can be -O- so as to form the anhy-
dride. The specific identity of any X or X' group which
is not one of the above is not critical so long as its
presence does not prevent the remaining group from enter-
ing into acylation reactions. Preferably, however, X
and X' are each such that both carboxyl functions of the
succinic group (i.e., both -C(O)X and -C(O)X' can enter
into acylation reactions.
One of the unsatisfied valences in the grouping
--C--C--
of Formula I forms a carbon carbon bond with a carbon
atom in the substituent group. While other such unsatis-
fied valence may be satisfied by a similar bond with the
same or different substituent group, all but the said
one such valence is usually satisfied by hydrogen; i.e.,
-H.
The substituted succinic acylating agents are
characterized by the presence within their structure of
an average of at least 1.3 succinic groups (that is,
groups corresponding to Formula I3 for each equivalent
weight of substituent groups. For purposes of this
invention, the equivalent weight of substituent groups
is deemed to be the number obtained by dividing the Mn
value of the polyalkene from which the substituent is
~?~
derived into the total weight of the substituent groups
present in the substituted succinic acylating agents.
Thus, if a substituted succinic acylating agent is
characterized by a total weight of substituent group of
40,000 and the Mn value for the polyalkene from which
the substituent qroups are derived is 2000, then that
substituted succinic acylating agent is characterized by
a total of 20 (40,000/2000=20) equivalent weights of
substituent groups. Therefore, that particular succinic
acylating agent must also be characterized by the pres-
ence within its structure of at least 26 succinic groups
to meet one of the requirements of the succinic a~yla-
ting agents used in this invention.
i Another requirement for the substituted succin-
ic acylating agents is that the substituent groups must
have been derived from a polyalkene characterized by an
Mw/Mn value of at least about 1.5. The upper limit of
Mw/Mn will generally be about 4.5. Values of from 1.5
to about 4.5 are particularly useful.
Polyalkenes having the Mn and Mw values discuss-
ed above are known in the art and can be prepared accord-
ing to conventional procedures. For example, some of
t~hese polyalkenes are described and exemplified in U.S.
Patent 4,234,435, and the disclosure of this patent
rela~ive to such polyalkenes is hereby incorporated ~y
reference. Several such polyalkenes, especiaIly polybut-
enes, are commercially available.
In one preferred embodiment, the succinic
groups will normally correspond to the formula
-CH - C(O)R
CH2 ~ C(O)R' (II)
~7~
-18-
wherein R and R' are each independently selected from
the group consisting of -OH, -Cl, -O-lower alkyl, and
when taken together, R and R' are -O-. In the latter
case, the succinic group is a succinic anhydride group.
All the succinic groups in a particular succinic acylat-
ing agent need not be the same, but they can be the
same. Preferably, the succinic groups will correspond
to
-CH - C ~ OH -CH - C
C~2- C ~ O~ or ¦ \ O (III)
(A) (B)
and mixtures of (III(A)) and (III(B)). Providi~g substi-
tuted succinic acylating agents wherein the succinic
groups are the same or different is within the ordinary
skill of the art and can be accomplished through conven-
tional procedures such as treating the substituted suc-
cinic acylating agents themselves (for example, hydrolyz-
ing the anhydride to the free acid or converting the
free acid to an acid chloride with thionyl chloride)
and/or selecting the appropriate maleic or fumaric react-
ants.
As previously mentioned, the minimum number of
succinic groups for each equivalent weight of substitu-
ent group is 1.3. The maximum number generally will not
exceed 4.5. Generally the minimum will be about 1.4 suc-
cinic groups for each equivalent weight of substituent
group. A range based on this minimum is at least 1.4 to
about 3.5, and more specifically about 1.4 to about 2.5
succinic groups per equivalent weight of substituent
groups.
~? ~
--1 9--
In addition to preferred substituted succinic
groups where the preference depends on the number and
identity of succinic ~roups for each equivalent weight
of substituent groups, still further preferences are
based on the identity and characterization of the poly-
alkenes from which the substituent groups are derived.
With respect to the value of Mn for example, a
minimum of about 1300 and a maximum of about 5000 are
preferred with an Mn value in the range of from about
1500 to about 5000 also being preferred. A more prefer-
red Mn value is one in the range of from about 1500 to
about 2800. A most preferred range of Mn values is from
about 1500 to about 2400.
Before proceeding to a further discussion of
the polyalkenes from which the substituent groups are
derived, it should be pointed out that these preferred
characteristics of the succinic acylating agents are
intended to be understood as being both independent and
dependent. They are intended to be independent in the
sense that, for example, a preference for a minimum of
1.4 or 1.5 succinic groups per equivalent weight of sub-
stituent groups is not tied to a more preferred value of
~n or Mw/Mn. They are intended to be dependent in the
sense that, for example, when a preference for a minimum
of 1.4 or 1.5 succinic groups is combined with more
preferred values of Mn and/or Mw/Mn, the combination of
preferences does in fact describe still further more
preferred embodiments of the invention. Thus, the var-
ious parameters are intended to stand alone with respect
to the particular parameter being discussed but can also
be combined with other parameters to identify further
preferences. This same concept is intended to apply
throu~hout the specification with respect to the des-
~n~78~9
-20-
cription of preferred values, ranges, ratios, reactants,
and the like unless a contrary intent is clearly demon-
strated or apparent.
In one embodiment, when the Mn of a polyalkene
is at the lower end of the range, e.g., about 1300, the
ratio of succinic groups to substituent groups derived
from said polyalkene in the acylating agent is prefer-
ably higher than the ratio when the Mn is, for example,
1500. Conversely when the Mn of the polyalkene is
higher, e.g., 2000, the ratio may be lower than when the
Mn of the polyalkene is, e.g., 1500.
The polyalkenes from which the substituent
groups are derived are homopolymers and interpolymers of
polymerizable olefin monomers of 2 to about 1~ carbon
atoms; usually 2 to about 6 carbon atoms. The interpoly-
mers are those in which two or more olefin monomers are
interpolymerized according to well-known conventional
procedures to form polyalkenes having units within their
structure derived from each of said two or more olefin
monomers. Thus, "interpolymer(s)" as used herein is
inclusive of copolymers, terpolymers, tetrapolymers, and
the like. As will be apparent to those of ordinary
skill in the art, the polyalkenes from which thP substi-
tuent groups are derived are often conventionally refer-
red to as "polyolefin(s)".
The olefin monomers from which the polyalkenes
are derived are polymerizable olefin monomers character-
ized by the presence of one or more ethylenically unsat-
urated groups (i.e., >C=C<); that is, they are monoole-
finic monomers such as ethylene, propylene, butene-1,
isobutene, and octene-1 or polyolefinic monomers (usual-
ly diolefinic monomers) such as butadiene-1,3 and iso-
prene.
Z~7~9
-21-
These olefin monomers are usually polymerizable
terminal olefins; that is, olefins characterized by the
presence in their structure of the group >C=CH2. How-
ever, polymerizable internal olefin monomers (sometimes
referred to in the literature as medial olefins) charac-
terized by the presence within their structure of the
group
--C--C=C--C--
can also be used to form the polyalkenes. When internal
olefin monomers are employed, they normally will be em-
ployed with terminal olefins to produce polyalkenes
which are interpolymers. For purposes of this invention,
when a particular polymerized olefin monomer can be
classified as both a terminal olefin and an internal
olefin, it will be deemed to be a terminal olefin. Thus,
1,3-pentadiene (i.e., piperylene) is deemed to be a
terminal olefin for purposes of this invention.
Some of the substituted succinic acylating
agents (B-1) useful in preparing the carboxylic esters
(B) are known in the art and axe described in, for exam-
p~le, U.S. Patent 4,234,435, the disclosure of which is
hereby incorporated by reference. The acylating agents
described in the '435 patent are characterized as con-
taining substituent groups derived from polyalkenes
having an Mn value of about 1300 to about 5000, and an
Mw/Mn value of about 1.5 to about 4.
There is a general preference for aliphatic,
hydrocarbon polyalkenes free from aromatic and cycloali-
phatic groups. Within this general preference, there is
a further preference for polyalkenes which are derived
from the group consisting of homopolymers and interpoly-
~` ~L7~9
-22-
mers of terminal hydrocarbon olefins of 2 to about 16
carbon atoms. This further preference is qualified by
the proviso that, while interpolymers of terminal ole-
fins are usually preferred, interpolymers optionally
containing up to about 40~ of polymer units derived from
internal olefins of up to about 16 carbon atoms are also
within a preferred group. A more preferred class of
polyalkenes are those selected from the group consisting
of homopolymers and interpolymers of terminal olefins of
2 to about 6 carbon atoms, more preferably 2 to 4 carbon
atoms. However, another preferred class of polyalkenes
are the latter more preferred polyalkenes optionally
containing up to about 25% of polymer units derived from
internal olefins of up to about 6 carbon atoms.
Obviously, preparing polyalkenes as described
above which meet the various criteria for Mn and Mw/Mn
is within the skill of the art and does not comprise
part of the present invention. Techniques readily appar-
ent to those in the art include controlling polymeriza-
tion temperatures, regulating the amount and type of
polymerization initiator and/or catalyst, employing
chain terminating groups in the polymerization proced-
ure, and the like. Other conventional techniques such
as stripping (including vacuum stripping) a very light
end and/or oxidatively or mechanically degrading high
molecular weight polyalkene to produce lower molecular
weight polyalkenes can also be used.
In preparing the substituted succinic acylating
agents of this invention, one or more of the above-des-
cribed polyalkenes is reacted with one or more acidic
reactants selected from the group consisting of maleic
or fumaric reactants of the general formula
2'~7819
--23--
X(O)C-CH=CH-C(O~X' (IV)
wherein X and X' are as defined hereinbefore in Formula
I. Preferably the maleic and fumaric reactants will be
one or more compounds corresponding to the formula
RC(O)-CH=CH-C(O)R' (V)
wherein R and R' are as previously defined in Formula II
herein. Ordinarily, the maleic or fumaric reactants
will be maleic acid, fumaric acid, maleic anhydride, or
a mixture of two or more of these. The maleic reactants
are usually preferred over the fumaric reactants because
the former are more readily available and are, in gen-
eral, more readily reacted with the polyalkenes (or
derivatives thereof) to prepare the substituted succinic
acylating agents of the present invention. The especial-
ly preferred reactants are maleic acid, maleic anhy-
dride, and mixtures of these. Due to availability and
ease of reaction, maleic anhydride will usually be em-
ployed.
Examples of patents describing various proce-
dures for preparing useful acylating agents include U.S.
Patents 3,215,707 (Rense); 3,219,666 (Norman et al);
3,231,587 (Rense); 3,912,764 (Palmer); 4,110,349
(Cohen); and 4,234,435 (Meinhardt et al); and U.K.
1,440,219. The disclosures of these patents are hereby
incorporated by reference.
For convenience and brevity, the term "snaleic
reactant" is often used hereinafter. When used, it
should be understood that the term is generic to acidic
reactants selected ~rom maleic and fumaric reactants
corresponding to Formulae (IV) and (V) above including a
mixture of such reactants.
~ ~L7~D
-24-
The acylating reagents described above are
intermediates in processes for preparing the carboxylic
derivative compositions ~B) comprising reacting (B-1)
one or more acylating reagents with (B-2) at least one
amino compound characterized by the presence within its
structure of at least one HN< group.
The amino compound (B-2) characterized by the
presence within its structure of at least one HN< group
can be a monoamine or polyamine compound. Mixtures of
two or more amino compounds can be used in the reaction
with one or more acylating reagents of this invention.
Preferably, the amino` compound contains at least one
primary amino group (i.e., -NH2) and more preferably
the amine is a polyamine, especially a polyamine con-
tai.ning at least two -NH- groups, either or both of
which are primary or secondary amines. The amines may
be aliphatic, cycloaliphatic, aromatic or heterocyclic
amines. The polyamines not only result in carboxylic
acid derivative compositions which are usually more
effective as dispersant/detergent additives, relative to
derivative compositions derived from monoamines, but
these preferred polyamines result in carboxylic deriva-
tive compositions which exhibit more pronounced V.I.
improving properties.
Among the preferred amines are the alkylene
polyamines, including the polyalkylene polyamines. The
alkylene polyamines include those conforming to the
formula
3 3
R N-(U-N) -R (VI)
R R
~ ';'8~
-25-
wherein n is from 1 to about 10; each R3 is indepen-
dently a hydrogen atom, a hydrocarbyl group or a
hydroxy-substituted or amine-substituted hydrocarbyl
group having up to about 30 atoms, or two R3 groups on
different nitrogen atoms can be joined together to form
a U group, with the proviso that at least one R3 group
is a hydrogen atom and U is an alkylene ~roup of about 2
to about 10 carbon atoms. Preferably U is ethylene or
propylene. Especially preferred are the alkylene poly-
amines where each R3 is hydrogen or an amino-substi-
tuted hydrocarbyl group with the ethylene polyamines and
mixtures of ethylene polyamines being the most prefer-
red. Usually n will have an average value of from about
2 to about 7. Such alkylene polyamines include methyl-
ene polyamine, ethylene polyamines, butylene polyamines,
propy.lene polyamines, pentylene polyamines, hexylene
polyamines, heptylene polyamines, etc. The higher homo-
logs of such amines and related amino alkyl-substituted
piperazines are also included.
Alkylene polyamines useful in preparing the
carboxylic derivative compositions (B) include ethylene
diamine, triethylene tetramine, propylene diamine, tri-
methylene diamine, hexamethylene diamine, decamethylene
diamine, hexamethylene diamine, decamethylene diamine,
octamethylene diamine, di(heptamethylene) triamine,
tripropylene tetramine, tetraethylene pentamine, trimeth-
ylene diamine, pentaethylene hexamine, di(trimethylene)-
triamine, N-(2-aminoethyl)piperazine, 1,4-bis(2,aminoeth-
yl)piperazine, and the like. Higher homologs as are
obtained by condensing two or more of the above-illus-
trated alkylene amines are useful, as are mixtures of
two or more of any of the afore-described polyamines.
2n~7sl~
-26- -
Ethylene polyamines, such as those mentioned
above, are especially useful for reasons of cost and
effectiveness. Such polyamines are desc~ibed in detail
under the heading "Diamines and Higher Amines" in The
Encyclopedia of Chemical Technology, Second Edition,
Kirk and Othmer, Volume 7, pages 27-~9, Interscience
Publishers, Division of John Wiley and Sons, 1965, which
is hereby incorporated by reference for the disclosure
of useful polyamines. Such compounds are prepared most
conveniently by the reaction of an alkylene chloride
with ammonia or by reaction of an ethylene imine with a
ring-opening reagent such as ammonia, etc. These reac-
tions result in the production of the somewhat complex
mixtures of alkylene polyamines, including cyclic conden-
sation products such as piperazines. The mixtures are
particularly useful in preparing carboxylic derivative
(B) useful in this invention. On the other hand, quite
satisfactory products can also be obtained by the use of
pure alkylene polyamines.
Other useful types of polyamine mixtures are
those resulting from stripping of the above-described
polyamine mixtures. In this instance, lower molecular
weight polyamines and volatile contaminants are removed
from an alkylene polyam ne mixture to leave as residue
what is often termed "polyamine bottoms". In general,
alkylene polyamine bottoms can be characterized as
havinq less than two, usually less than 1% (by weight~
material boiling below about 200C. In the instance of
ethylene polyamine bottoms, which are readily available
and found to be quite useful, the bottoms contain less
than about 2% ~by weight) total diethylene triamine
(DETA) or triethylene tetramine (TETA). A typical sample
of such ethylene polyamine bottoms obtained from the Dow
~0~7~
-27-
Chemical Company of Freeport, Texas designated "E-l00"
showed a specific gravity at 15.6C of 1.0168, a percent
nitrogen by weight of 33.15 and a viscosity at 40C of
121 centistokes. Gas chromatography analysis of such a
sample showed it to contain about 0.93% "Light Ends"
(most probably DETA), 0.72% TETA, 21.74% tetraethylene
pentamine and 76.61% pentaethylene hexamine and higher
(by weight). These alkylene polyamine bottoms include
cyclic condensation products such as piperazine and high-
er analogs of diethylenetriamine, triethylenetetramine
and the like.
Other polyamines which can be reacted with the
acylating agents (B-1) in accordance with this invention
are described in, for example, U.S. Patents 3,219,666
and 4,234,435, and these patents are hereby incorporated
by reference for their disclosures of amines which can
be reacted with the acylating agents described above to
form the carboxylic derivatives (B) of this invention.
The carboxylic derivative compositions (B) pro-
duced from the acylating reagents (B-1) and the amino
compounds (s-2) described hereinbefore comprise acylated
amines which include amine salts, amides, imides and
imidazolines as well as mixtures thereof. To prepare
the carboxylic acid derivatives from the acylating rea-
gents and the amino compounds, one or more acylating
reagents and one or more amino compounds are heated,
optionally in the presence of a normally liquid, substan-
tially inert organic liquid solvent/diluent, at tempera-
tures in the range of about ~0C up to the decomposition
point (where the decomposition point is as pr~viously
defined) but normally at temperatures in the range of
about 100C up to about 300C provided 300C does not
exceed the decomposition point. Temperatures of about
;~C~7E~
-28-
125C to about 250C are normally used. The acylating
reagent and the amino compound are reacted in amounts
suf~icient to provide from about one-half equivalent up
to about 2 moles of amino compound per equivalent of
acylating reagent.
Because the acylating reagents (B-1) can be re-
acted with the amine compounds (B-2) in the same manner
as the high molecular weight acylating agents of the
prior art are reacted with amines, U.S. Patents
3,172,892; 3,219,666; 3,272,746; and 4,234,435 are
expressly incorporated herein by reference for their dis~
closures with respect to the procedures applicable to
reacting the acylating reagents with the amino compounds
as described above.
In order to produce carboxylic derivative com-
positions exhibiting viscosity improving capabilities,
it has been found generally necessary to react the
acylating reagents with polyfunctional amine reactants.
For example, polyamines having two or more primary
and/or secondary amino groups are preferred. Obviously,
however, it is not necessary that all of the amino com-
pound reacted with the acylating reagents be polyfunc-
tional. Thus, combinations of mono and polyfunctional
amino compounds be used.
In one embodiment, the acylating agent is react-
ed with from about 0.70 equivalent to less than 1 equiv-
alent (e.g., about 0.95 equivalent3 of amino compound,
per equivalent of acylating agent. The lower limit on
the equivalents of amino compound may be 0.75 or even
0.80 up to about 0.90 or 0.95 equivalent, per equivalent
of acylating agent. Thus narrower ranges of equivalents
of acylating agents (B-13 to amino compounds (B-23 may
be from about 0.70 to about 0.90 or about 0.75 to about
Z(-~7~9
-29-
0.90 or about 0.75 to about 0.85. It appears, at least
in some situations, that when the equivalent of amino
compound is about 0.75 or less, per equivalent of acylat-
ing agent, the effectiveness of the carboxylic deriva-
tives as dispersants is reduced. In one embodiment, the
relative amounts of acylating agent and amine are such
that the carboxylic derivative preferably contains no
free carboxyl groups.
In another embodiment, the acylating agent is
reacted with from about 1.0 to about 1.1 or up to about
1.5 equivalents of amino compound, per equivalent of
acylatinq agent. Increasing amounts of the amino com-
pound also can be used.
The amount of amine compound (B-2) within the
above ranges that is reacted with the acylating agent
(B-1) may also depend in part on the number and type of
nitrogen atoms present. For example, a smaller amount
of a polyamine containing one or more -NH2 groups is
required to react with a ~iven acylating agent than a
polyamine having the same number of nitrogen atoms and
fewer or no -NH2 groups. One -N~2 group can react
with two -COOH groups to form an imide. If only second-
ary nitrogens are present in the amine compound, each
>NH group can react with only one -COOH group. Accord-
ingly, the amount of polyamine within the above ranges
to be reacted with the acylating agent to form the car-
boxylic derivatives of the invention can be readily
determined from a consideration of the number and types
of nitrogen atoms in the polyamine (i.e.., -NH2, >NH,
and >N~
In addition to the relative amounts of acylat-
ing agent and amino compound used to form the carboxylic
derivative composition (B), other features of the carbox-
8~g
-30-
ylic derivative compositions used in this invention are
the Mn and the Mw/Mn values of the polyalkene as well as
the presence within the acylating agents of an average
of at least 1.3 succinic groups for each equivalent
weight of substituent groups. When all of these fea-
tures are present in the carboxylic derivative composi-
tions (B), the lubricating oil compositions of the
present invention exhibit novel and improved properties,
and the lubricating oil compositions are characterized
by improved performance in combustion engines.
The ratio of succinic groups to the equivalent
weight of substituent group present in the acylating
agent can be determined from the saponification number
of the reacted mixture corrected to account for unreact-
ed polyalkene present in the reaction mixture at the end
of the reaction (generally referred to as filtrate or
residue in the following examples). Saponification num-
ber is determined using the ASTM D-94 procedure. The
formula for calculating thè ratio from the saponifica-
tion number is as follows:
Ratio = (Mn)(Sae No.,corrected)
112,200-98(Sap No.,corrected)
The corrected saponification number is obtained
by dividing the saponification number by the percent of
the polyalkene that has reacted. For example, if 10% of
the polyalkene did not react and the saponification
number of the filtrate or residue is 95, the corrected
saponification number is 95 divided by 0.90 or 105.5.
The preparation of the acylating agents is
illustrated in the following Examples 1-3 and the prepar-
ation of the carboxylic acid derivative composltions (B)
is illustrated by the following Examples B-1 to B-26.
7~
-31-
In the following examples, and elsewhere in the specifi-
cation and claims, all percentages and parts are by
weight, temperatures are in degrees Celsius and pres-
sures are at or near atmospheric unless otherwise clear-
ly indicated.
AcYlatinq Aqents:
Example 1
A mixture of 510 parts (0.28 mole) of polyisobu-
tene (Mn=1845; Mw=5325) and 59 parts (0.59 mole) of
maleic anhydride is heated to 110C. This mixture is
heated to 190C in 7 hours during which 43 parts (0.6
mole) of gaseous chlorine is added beneath the sur~ace.
At 190-192C an additional 11 parts (0.16 mole) of
chlorine is added over 3.5 hours. The reaction mixture
is stripped by heating at 190-1 93C with nitrogen blow-
ing for 10 hours. The residue is the desired pol~iso-
butene-substituted succinic acylating agent having a
saponification equivalent number of 87 as determined by
ASTM procedure D-94.
Example 2
A mixture of 1000 parts (0.495 mole) of polyiso-
butene (Mn=2020; Mw=6049) and 115 parts (1.17 moles) of
maleic anhydride is heated to 110C. This mixture is
heated to 184C in 6 hours during which 85 parts (1.2
moles) of gaseous chlorine is added beneath the surface.
At 184-189C an additional 59 parts (0.83 mole) of chlor-
ine is added over 4 hours. The reaction mixture is strip-
ped ~y heating at 186-190C with nitrogen blowing ~or 26
hours. The residue is the desired polyisobutene-substi-
tuted succinic acylating agent having a saponification
equivalent number of 87 as determined by ASTM procedure
D-9~.
~n3L7819
-32-
Example 3
A mixture parts of polyisobutene chloride, pre-
pared by the addition of 251 parts of gaseous chlorine
to 3000 parts of polyisobutene (Mn=1696; Mw=6594) at
80C in 4.66 hours, and 345 parts of maleic anhydride is
heated to 200C in 0.5 hour. The reaction mixture is
held at 200-224C for 6.33 hours, stripped at 210C
under vacuum and filtered. The filtrate is the desired
polyisobutene-substituted succinic acylating agent hav-
ing a saponification equivalent number of 94 as determin-
ed by ASTM procedure D-94.arboxYllc Derivative Com~ositions tB):
~xample B-1
A mixture is prepared by the addition of 10.2
parts (0.2~ equivalent) o a commercial mixture of
ethylene polyamines having from about 3 to about 10
nitrogen atoms per molecule to 113 parts of mineral oil
and 161 parts (0.25 equivalent) of the substituted
succinic acylating agent prepared in Example 1 at 138C.
The reaction mixture is heated to 150C in 2 hours and
stripped by blowing with nitrogen. The reaction mixture
is filtered to yield the product as an oil solution.
~xample B-2
A mixture is prepared by the addition of 57
parts (1.38 equivalents) of a commercial mixture of
ethylene polyamines having from about 3 to 10 nitrogen
atoms per molecule to 1067 parts of mineral oil and 893
parts (1.38 e~uivalents) of the substituted succinic
acylating agent prepared in Example 2 at 140-145C. The
reaction mixture is heated to 155C in 3 hours and strip-
ped by blowing with nitrogen The reaction mixture is
filtered, and the filtrate as the desired product.
~0~'7~
-33-
Example B-3
A mixture of 1132 parts of mineral oil and 709
parts (1.2 equivalents) of a substituted succinic acylat-
in~ aqent prepared as in Example 1 is prepared, and a
solution of 56.8 parts of piperazine (1.32 equivalents)
in 200 parts of water is added slowly from a dropping
funnel to the above mixture at 130-140C over approxi-
mately ~ hours. Heating is continued to 160C as water
is removed. The mixture is maintained at 160-165C for
one hour and cooled overnight. After reheating the mix-
ture to 160C, the mixture is maintained at this tempera-
ture for 4 hours. Mineral oil (270 parts) i5 added, and
the mixture is filtered at 150C through a filter aid.
The filtrate is the desired product containin~ 65~ oil
and 0.65~ nitrogen (theory, 0.86%).
Example B-4
A mixture of 1968 parts of mineral oil and 1508
parts (2.5 equivalents) a substituted succinic acylating
agent prepared as in Example 1 is heated to 145C where-
upon 125.6 parts (3.0 equivalents) of a commercial mix-
ture of ethylene polyamines as used in Example B-1 are
added over a period of 2 hours while maintaining the
reaction temperature at 145-150C. The reaction mixture
is stirred for 5.5 hours at 150-152C while blowing with
nitrogen. The mixture is fiItered at 150C with a fil-
ter aid. The filtrate is the desired product containing
55% oil and 1.20~ nitrogen (theory, 1.17).
Example B-5
A mixture of 1503 parts of mineral oil and 1220
parts (2 equivalents) of a substituted succinic acylat-
ing agent prepared as in Example 1 is heated to 110C
whereupon 120 parts (3 equivalents) of a commercial mix-
ture of ethylene polyamines of the type used in Example
~3 ~ 9
B-1 are added over a period of about 50 minutes. The
reaction mixture is stirred an additional 30 minutes at
110C, and the temperature is then raised to and main-
tained at about 151C for 4 hours. A filter aid is
added and the mixture is filtered. The filtrate is the
desired product containing 53.2% oil and 1.94~ nitrogen
(theory, 1.49J.
Example B-6
A mixture of 3111 parts of mineral oil and 844
parts (21 equivalents) of a commercial mixture of ethyl-
ene polyamine as used in Example B-1 is heated to 1~0C
whereupon 3885 parts (7.0 equivalents) of a substituted
succinic acylating agent prepared as in Example 1 are
added over a period of about 1.75 hours as the tempera-
ture increases to about 150C. While blowing with nitro-
gen, the mixture is maintained at 150-155C for a period
of about 6 hours and thereafter filtered with a filter
aid at 130C. The filtrate is the desired product
containing 40% oil and 3.5% nitrogen (theory, 3.78).
Example B-7
A mixture is prepared by the addition of 18.2
parts (0.433 equivalent) of a commercial mixture of
ethylene polyamines having from about 3 to 10 nitrogen
atoms per molecule to 392 parts of mineral oil and 348
parts (0.52 equivalent) of the substituted suecinic acyl-
ating agent prepared in Example 2 at 140C. The reac-
tion mix~ure is heated to 150C in 1.8 hours and strip-
ped by blowing with nitrogen. The reaction mixture is
filtered to yield the filtrate which is the desired
product containing 55% oil.
Example B-8
An appropriate size flask fitted with a stir-
rer, nitrogen inlet tube, addition funnel and Dean-
Zf~
-35-
Stark trap/condenser is charged with a mixture of 2483
parts acylating agent (4.2 equivalents) as described in
Example 3, and 1104 parts oil. This mixture is heated
to 210C while nitrogen was slowly bubbled through the
mixture. Ethylene polyamine bottoms (134 parts, 3.14
equivalents) are slowly added over about one hour at
this temperature. The temperature is maintained at about
210C or 3 hours and then 3688 parts oil is added to
decrease the temperature to 125C. After storage at
138C for 17.5 hours, the mixture is filtered through
diatomaceous earth to provide the desired acylated amine
bottoms containing 65% oil.
Example B-9
A mixture of 3660 parts (~ equivalents) of a
substituted succinic acylating agent prepared as in
Example 1 in 4664 parts of diluent oil is prepared and
heated at about 110C whereupon nitrogen is blown
through the mixture. To this mixture there are then
added 210 parts (5.25 equivalents) of a commercial
mixture of ethylene polyamines containing from about 3
to about 10 nitrogen atoms per molecule over a period of
one hour and the mixture is maintained at 110C for an
additional 0.5 hour. After heating for 6 hours at 155C
while removing water, a filtrate is added and the reac-
tion mixture is filtered at about 150C. The filtrate
is the desired product.
Example B-10
The general procedure of Example B-9 is repeat-
ed with the exception that 0.8 equivalent of a substi-
tuted succinic acylating agent as prepared in Example 1
is reacted with 0.67 equivalent of the commercial mix-
ture of ethylene polyamines. The product obtained in
this manner is an oil solution containing 55% diluent
oil.
~ D'8~
-36-
Example B-11
The general procedure of Example B-9 is repeat-
ed except that the polyamine used in this example is an
equi~alent amount of an alkylene polyamine mixture com-
prising 80% of ethylene polyamine bottoms from Union
Carbide and 20% of a commercial mixture of ethylene poly-
amines corresponding in empirical formula to diethylene
triamine. ~his polyamine mixture is characterized as
having an equivalent weight of about 43.3.
Example B-12
The general procedure of Example B-9 is repeat-
ed except that the polyamine utilized in this example
comprises a mixture of 80 parts by weight of ethylene
polyamine bottoms available from Dow and 20 parts by
weight of diethylenetriamine. This mixture of amines
has an equivalent weight of about 41.3.
Example B-13
A mixture of 444 parts (0.7 equivalent) of a
substituted succinic acylating agent prepared as in
Example 1 and 563 parts of mineral oil is prepared and
heated to 140C whereupon 22.2 parts of an ethylene
polyamine mixture corresponding in empirical formula to
triethylene tetramine (0.58 equivalent) are added over a
period of one hour as the temperature is maintained at
140C. The mixture is blown with nitrogen as it is
heated to 150C and maintained at this temperature for 4
hours while removing water. The mixture then is filter-
ed throuqh a filter aid at about 135C, and the filtrate
is the desired product comprising about 55% of mineral
oil.
Example B-14
A mixture of 422 parts (0.7 equivalent) of a
substituted succinic acylating agent prepared as in
7~3~9
-37-
Example 1 and 188 parts of mineral oil is prepared and
heated to 210C whereupon 22.1 parts (0.53 equiYalent)
of a commercial mixture of ethylene polyamine bottoms
from Dow (E-100) are added over a period of one hour
blowing with nitrogen. The temperature then is increas-
ed to about 210-216C and maintained at this temperature
for 3 hours. Mineral oil (625 parts) is added and the
mixture is maintained at 135C for about 17 hours where-
upon the mixture is filtered and the filtrate is the
desired product containin~ 65% oil.
Example B-15
A mixture of 414 parts (0.71 equivalent) of a
substituted succinic acylating agent prepared as in Exam-
ple 1 and 184 parts of mineral oil is prepared and heat-
ed to about 80C whereupon 22.4 parts (0.534 equivalent)
of melamine are added. The mixture is heated to 160C
over a period of about 2 hours and maintained at this
temperature for 5 hours. After cooling overnight, the
mixture is heated to 170C over 2.5 hours and to 215C
over a period of 1.5 hours. The mixture is maintained
at about 215C for about 4 hours and at about 220C for
6 hours. After cooling overnight, the reaction mixture
is filtered at 150C through a filter aid. The filtrate
is the desired product containing 30% mineral o.il.
Example B-16
A mixture of 414 parts (0.71 equivalent) of a
substituted acylating agent prepared as in Example 1 and
184 parts of mineral oil is heated to 210C whereupon 21
parts (0.53 equivalent) o~ a commercial mixture of ethyl-
ene polyamine corresponding in empirical formula to
tetraethylene pentamine are added over a period of 0.5
hour as the temperature is maintained at about 210-
217C. Upon completion of the addition of the poly-
;Z n~78~9
-38-
amine, the mixture is maintained at 217C for 3 hours
while blowing with nitrogen. Mineral oil is added (613
parts) and the mixture is maintained at about 135C for
17 hours and filtered. The filtrate is the desired
product containing 65% mineral oil.
(C) Manqanese Compound.
The lubricating oil compositions of the present
invention contain at least one manganese compound in an
amount which is sufficient to provide from 1 to about
500 ppm of manganese as metal, provided that the mangan-
ese compound is not a neutral manganese dihydrocarbyl
phosphorodithioate. In one embodiment, the manganese
compounds are soluble in the lubricating oil composi-
tions of the invention. The manganese compounds (C) gen-
erally are salts of acidic materials, and in particular,
salts of carboxylic acids, sulfonic acids, and phenols.
In another embodiment, the amount of manganese compound
in the oil will provide from about 50 to about 300 ppm
of manganese as metal. The manganese compounds may be
neutral manganese compounds or "overbased" manganese
compounds, and the overbased manganese compounds general-
ly are preferred. The term "overbased" as applied to
'che manganese compounds utilized in the present inven-
tion is an indication that the compounds contain more
manganese than is required to neutralize the acid. Thus,
overbased manganese salts contain more than one equiva-
lent of metal per equivalent of acid. Overbased magne-
sium salts of acidic materials such as carboxyli~ acids,
sulfonic acids, phenols and phosphorus acids are known
and have been described in the art. See, for example,
U.S. Patent 4,162,986 (Alkaitis); U.S. Patent 3,827,979
(Piotrowski et al); U.S. Patent 3,312,618 lLesuer et
al); U.S. Patents 2,616,904 and '905 (Aseff et al); and
;~S3~78~
-39-
U.S. Patent 4,252,659 (Ali). It should be noted that
although neutral manganese dihydrocarbyl
phosphorodithioates are not included in the lubricating
oil compositions of the present invention, overbased
manganese dihydrocarbyl phosphorodithioates are
contemplated as being useful manganese compounds.
The overbased manganese salts are preferred
because they pro~ide high manganese content with
retention of solubility and are useful, therefore, for
introducing high amounts of metal while minimizing the
amount of acidic compound introduced into the lubricat-
ing oil which merely serves as a carrier for the manga-
nese metal. As noted, the metal-to-acid mole ratios of
overbased manganese compounds is greater than 1 to 1 and
is generally greater than 2 to 1. The mole ratio of
metal-to-acid in overbased compounds often is referred
to as the Metal Ratio.
The organic acids used in the preparation of
the manganese salts contain carbon atoms and include
carboxylic acids, particularly those containing from 1
to about 30 carbon atoms, sulfonic acids, particularly
those containing an aromatic ring structure substituted
with one or more alkyl groups of from 4 to about 22
carbon atoms, phenolic compounds, particularly hydrocar-
bon-substituted phenols; and when the manganese compound
is an o~erbased compound, phosphorus compouDds contain-
ing within their structures, one or more organic groups
of from 1 to about 30 or more carbon atoms. All of
these acidic materials are well known in the art.
The carboxylic acids can be aliphatic, cycloali-
phatic, or aromatic mono- and polycarboxylic acids.
Monocarboxylic acids include C1_7 lower acids (acetic,
propionic, etc) and higher C8~ acids (e.g., octanoic,
-40-
decanoic, etc.) as well as the well known fatty acids of
about 12-30 carbon atoms. The fatty acids are often
mixtures or straight and branched chain acids contain-
ing, for example, from 5% to about 30% straight chain
acids and about 70% to about 95% (mole) branched chain
acids. Other commercially available fatty acid mixtures
containing much higher proportions of straight chain
acids are also useful. Mixtures produced from dimeriza-
tion of unsaturated fatty acids can also be used.
Higher carboxylic acids include the well-known
dicarboxylic acids made by alkylating maleic anhydride
or its derivatives. The products of such reactions are
hydrocarbon substituted succinic acids, anhydrides, and
the like. Lower molecular weight dicarboxylic acids,
such as the polymethylene bridged acids Iglutaric,
adipic, and the like), can also be used to make the
salts of this invention as well as the lower molecular
weight substituted succinic acids such as tetrapropenyl
succinic acid and its analogs of to about C30 substi-
tuted acids.
Higher molecular weig~t substituted succinic
anhydrides, acids, and analogs described above in the
preparation of the dispersants (B) are also useful in
making the manganese salts of this invention.
The aliphatic acids generally contain at least
8 carbon atoms and preferably at least 12 carbon atoms.
Usually they have no more than about 400 carbon atoms.
Generally, if the aliphatic carbon chain is branched,
the acids are more oil-soluble for any given carbon
atoms content. The cycloaliphatic and aliphatic carbox-
ylic acids can be saturated or unsaturated. Specific
examples include 2-ethylhexanoic acid, alpha~linolenic
acid, propylene-tetramer-substituted succinic acid,
~ 7~ ~
-41-
behenic acid, isostearic acid, pelargonic acid, capric
acid, palmitoleic acid, linoleic acid, lauric acid,
oleic acid, ricinoleic acid, undecylic acid, dioctylcy-
clopentane carboxylic acid, myristic acid, dilauryldeca-
hydronaphthalene carboxylic acid, stearyl-octahydro-
indene carboxylic acid, palmitic acid, commercially
available mixtures of two or more carboxylic acids such
as tall oil acids, rosin acids, and the like.
The manganese salts also can be of oil-soluble
organic sulfur acids such as sulfonic, sulfamic, thiosul-
fonic, sulfinic, sulfenic, partial ester sulfuric, sul-
furous and thiosulfuric acid. Generally they are salts
of carboxylic or aliphatic sulfonic acids.
Examples of such carbocyclic or aliphatic sul-
fonic acids are mahogany sulfonic acids; bright stock
sulfonic acids; sulfonic acids derived from lubricating
oil ~raction having a Saybolt Viscosity from about 1~0
seconds at 100F to about 200 seconds at 210F; petrola-
tum sulfonic acids; mono- and polywax substituted sulfon-
ic and polysulfonic acids of, e.g., benzene, naphtha-
lene, phenol, diphenyl ether, naphthalene disulfide,
diphenyl amine, thiophene, alpha-chloronaphthalene,
etc.; other substituted sulfonic acids such as alkyl
benzene sulfonic acids (where the alkyl group has at
least 8 carbon atoms), cetylphenyl mono-sulfide sulfonic
acids, dicetyl thianthrene disulfonic acids, dilauryl
beta-naphthyl sulfonic acids, dicapryl nitronaphthalene
sulfonic ~cids and alkaryl sulfonic acids such as dode-
cylbenzene (bottoms) sulfonic acids. Dodecylbenzene
(bottoms) are principally mixtures of mono- and di-dode-
cylbenzenes.
The aliphatic sulfonic acids include paraffin
wax sulfonic acids, unsaturated paraffin wax sulfonic
-42-
acids, hydroxy-substituted paraffin wax sulfonic acids,
hexapropylene sulfonic acids, tetra-amylene sulfonic
acids, polyisobutene sulfonic acids wherein the polyiso-
butene contains from 20 to 7000 or more carbon atoms
chloro-substituted para~fin wax sulfonic acids, nitro-
paraffin wax sulfonic acids, etc.; cycloaliphatic sul-
fonic acids such as petroleum naphthene sulfonic acids,
cetyl cyclopentyl sulfonic acids, lauryl cyclohexyl sul-
fonic acids, bis-(di-isobutyl) cyclohexyl sulfonic
acids, mono- or poly-wax-substituted cyclohexyl sulfonic
acids, etc.
Further details concerning sulfonic acids used
herein can be found in U.S. Patents 2,616,905;
3,027,325; 3,312,618; 3,350,308; 3,471,403; 3,488,284;
3,595,790; 3,798,012; 3,829,381; 4,100,083; and
4,326,972. These are hereby incorporated by reference
for their disclosures in this regard.
Neutral and overbased manganese salts of
phenolic compounds (phenates) also are useful in the
lubricants of this invention. Hydrocarbon-substituted
phenols, sulfurized phenols and al~ylene (e.g., methyl-
ene) coupled phenols also are useful. Mixtures of
phenols can be used to prepare the manganese salts, or
mixtures of separately prepared manganese phenates can
be included in the lubricating oils of this invention.
Typically, the organic acids used to make the
manganese salts used in this invention are carboxylic
acids, sulfonic acids, or mixtures thereof. A particu-
larly useful group o~ manganese salts are those
described in U.S. Patent 4,162,986 to Alkaitis et al
which is hereby incorporated by reference ~or its
disclosure of manganese compositions and, particularly,
of manganese salts of organic acids which are useful in
the composition of the present invention.
-43-
It should be noted that the manganese salts
used in this invention are preferably overbased. Such
salts are known to the art. See, for example, the just
cited U.S. Patent 4,162,986 as well as the following
UOS~ ~ Patents 3,827,979; 4,252,659; 4,505,718; and
4,664,677. These patents are hereby incorporated by
reference for their disclosure of overbased manganese
salts of organic acids.
Particularly useful overbased manganese salts
of organic acids which are highly overbased manganese
metal organic compositions comprising manganese oxide-
hydroxide-carboxylate complexes wherein the metal con
tent is in chemical combination partly with oxygen in a
polynuclear metal oxide crystallite core and partly with
at least two different monocarboxylic acids or a mixture
of one or more monocarboxylic and monosulfonic acids con-
taining at least 2 carbon atoms as hydroxyl-metal-carbox-
ylate and hydroxyl-metal-sulfonate groups, at least one
of the acids being a monocarboxylic acid containing at
least 7 carbon atoms, and when the second acid is also a
monocarboxylic acid, the second acid contains a number
of carbon atoms in its longest chain differing by at
~east 2 carbon atoms from the total number of carbon
atoms in the other, at least a portion of the carboxyl-
ate and sulfonate groups being hydrogen bonded to oxygen
atoms of the core, and the remainder of the carbox~late
and sulfonate groups are unbonded and in equilibrium
with the bonded groups, and the ratio of total metal
moles to the total moles of organic acid is greater than
one. These preferred compositions and their method of
preparation are described in more detail in U.S. Patent
4,162,986, and in particular, in Cols. 8-14, and the
entire patent is hereby incorporated by reference for
its disclosure regarding such manganese salts~
Zf'~L~8~9
-~4-
Use~ul overbased manganese salts containing
high concentrations of manganese are commercially avail-
able froln Mooney Chemical Company: FOA g10~ liquid
carboxylate containing 40% manganese as metal; and 12%
Manganese CEM-ALL~.
Overbased manganese salts made from phosphorus
acids also are useful in the lubricants of the inven-
tion. The phosphorus acids may be represented by the
formula
(X1)a\
P(X3)X H ¦VII)
R2(X2)b/
wherein R1 and ~2 are each independently hydrocar-
bon groups;
X1, X2, X-~ and X4 are each independent-
ly oxygen or sulfur; and
a and b are each zero or 1.
The preparation of overbased manganese salts of
such phosphorus acids is described in the prior art such
as U.S. Patent 2,695,910 (Asseff et al). This patent is
incorporated herein for its disclosure o~ such overbased
manganese salts.
In addition to the above-described and required
carboxylic derivative dispersants (B) and manganese
compounds (C), the lubricants may, and generally do,
contain other additives to provide additional desirable
properties to the oil which are required for acceptable
performance in gasoline and diesel engines. Such addi-
tives include anti-wear additives such as metal phosphor-
odithioates, detergents, other dispersants including
carboxylic ester derivatives, etc.
Z~ 319
-45-
(D) Metal Dihydrocarbyl Phosphorodithioates.
In another embodiment, the oil compositions of
the present invention also contain tD) at least one
metal dihydrocarbyl phosphorodithioate characterized by
the formula
~R10~ ~ -
PSS ~ M (VIII)
~R20~ J
wherein R1 and R2 are each independently hydrocarbyl
groups containing from 3 to about 13 carbon atoms, M is
a metal, and n is an integer equal to the valence of M.
Generally, the oil compositions of the present
invention will contain varying amounts of one or more of
the above-identified metal phosphorodithioates such as
from about 0.01% to about 5% or from about 0.01% to
about 2~ by weight, and more generally from about 0.01
to about 1% by weight based on the weight of the total
oil composition. The metal phosphorodithioates are
added to the lubricating oil compositions of the inven-
tion to improve the anti-wear and antioxidant properties
of the oil compositions.
The hydrocarbyl groups R1 and R2 in the
phosphorodithioate of Formula VIII may be alkyl, cyclo-
alkyl, aralkyl or alkaryl groups, or a substantially
hydrocarbon group of similar structure. By "substantial-
ly hydrocarbon" is meant hydrocarbons which contain sub-
stituent groups such as ether, ester, nitro, or halogen
whic~ do not materially affect the hydrocarbon character
of the group.
Illustrative alkyl groups include isopropyl,
isobutyl, n-butyl, sec butyl, the various amyl groups,
~ 7~
--46--
n-hexyl, methylisobutyl carbinyl, heptyl, 2-ethylhexyl,
diisobutyl, i500ctyl, nonyl, behenyl, decyl, dodecyl,
tridecyl, etc. Illustrative lower alkylphenyl groups
include xylyl, cresyl, butylphenyl, amylphenyl, heptyl-
phenyl, etc. Cycloalkyl groups likewise are useful and
these include chiefly cyclohexyl and the lower alkyl-cy-
clohexyl radicals. Many substituted hydrocarbon groups
may also be used, e.g., chloropentyl, dichlorophenyl,
and dichlorodecyl.
The phosphorodithioic acids from which the
metal salts useful in this invention are prepared are
well known. Examples of dihydrocarbyl phosphorodithioic
acids and metal salts, and processes for preparing such
acids and salts are found in, for example, U~S. Patents
4,263,150; 4,289,635; 4,308,154; and 4,417,990. These
patents are hereby incorporated by reference for such
disclosures.
The phosphorodithioic acids are prepared by the
reaction of phosphorus pentasulfide with an alcohol or
phenol or mixtures of alcohols, mixtures of phenols or
mixtures of alcohols and phenols. The reaction involves
four moles of the alcohol or phenol per mole of phosphor-
us pentasulfide, and may be carried out within the temp-
erature range from about 50C to about ~00C, preferably
from about 50C to about 150C. Thus the preparation of
O,O-di-n-hexyl phosphorodithioic acid involves the reac-
tion of phosphorus pentasulfide with four moles of
n-hexyl alcohol at about 100C for about two hours.
Hydrogen sulfide is liberated and the residue is the
~efined acid. The preparation of the metal salt of this
acid may be effected by reaction with metal oxide.
Simply mixing and heating these two reactants is suffi-
cient to cause the reaction to take place and the result-
2~ ~78~
-47-
ing product is sufficiently pure for the purposes of
this invention.
The metal salts of dihydrocarbyl phosphorodi-
thioates which are useful in this invention include
those salts containing Group I metals, Group II metals,
aluminum, lead, tin, manganese, cobalt, and nickel. The
Group II metals, tin, iron, cobalt, lead, manganese,
nickel and copper are among the preferred metals. Zinc
and copper are especially useful metals. Examples of
metal compounds which may be reacted with the acid
include lithium oxide, lithium hydroxide, sodium hydrox-
ide, sodium carbonate, potassium hydroxide, potassium
carbonate, silver oxide, magnesium oxide, magnesium
hydroxide, calcium oxide, zinc hydroxide, zinc oxide,
copper oxide, strontium hydroxide, cadmium oxide, cad-
mium hydroxide, barium oxide, iron carbonate, copper
hydroxide, lead hydroxide, tin butylate, cobalt hydrox-
ide, nickel hydroxide, nickel carbonate, etc.
In some instances, the incorporation of certain
ingredients such as small amount~ of the metal acetate
or acetic acid in conjunction with the metal reactant
will facilitate the reaction and result in an improved
product. For example, the use of up to about 5~ of zinc
acetate in combination with the required amount of zinc
oxide facilitates the formation o~ a zinc phosphorodi-
thioate.
In one preferred embodiment, the alkyl groups
R1 and R2 are derived from secondary alcohols such
as isopropyl alcohol~ secondary butyl alcohol, 2-pentan-
ol, 4-methyl-2-pentanol, 2-hexanol, 3-hexanol, etc.
Especially useful metal phosphorodithioates can
be prepared from phosphorodithioic acids which in turn
are prepared by the reaction of phosphorus pentasulfide
2~3~78~
-48-
with mixtures of alcohols. In addition, the use of such
mixtures enables the utilization of lower cost alcohols
which in themselves may not yield oil-soluble phosphoro-
dithioic acids. Thus a mi~ture of isopropyl and hexyl
alcohols can be used to produce a very effective, oil-
soluble metal phosphorodithioate. For the same reason
mixtures of phosphorodithioic acids can be reacted with
the metal compounds to form less expensive, oil-soluble
salts.
The mixtures of alcohols may be mixtures of dif-
ferent primary alcohols, mixtures of different secondary
alcohols or mixtures of primary and secondary alcohols.
Examples of useful mixtures include: n-butanol and n-oc-
tanol; n-pentanol and 2-ethyl-1-hexanol; isobutanol and
n-hexanol; isobutanol and isoamyl alcohol; isopropanol
and 4-methyl-2-pentanol; isopropanol and sec-butyl alco-
hol; isopropanol and isooctyl alcohol; etc. Particularly
useful alcohol mixtures are mixtures of secondary alco-
hols containing at least about 20 mole percent of isopro-
pyl alcohol, and in a preferred embodiment, at least 40
mole percent of isopropyl alcohol.
In another embodiment, the lubricating oil com-
positions of the invention contain a mixture of metal
salts of dihydrocarbyl phosphorodithioic acids wherein
in at least one of the dihydrocarbyl phosphorodithioic
acids, one the hydrocarbyl groups (D-1) is an isopropyl
or secondary butyl group, the other hydrocarbyl group
(~-2) con'cains at least five carbon atoms, and at least
about 20 mole percent of all of the hydrocarbyl groups
present in (D) are isopropyl groups, secondary butyl
groups or mixtures thereof.
In yet another embodiment, the lubricating oil
compositions contain a mi~ture of metal salts of dihydro-
-49-
carbyl phosphorodithioic acids wherein in at least one
of the phosphorodithioic acids, one of the hydrocarbyl
groups (D-1) is an isopropyl or secondary butyl group
and the other hydrocarbyl group (D-2) contains at least
five carbon atoms, and the lubricating oil composition
contains at least about 0.05 weight percent of isopropyl
groups, secondary butyl groups, or mixtures thereof
derived from (D). In a further embodiment, the lubricat-
ing oil compositions of the invention may contain at
least about 0.08 weight percent of isopropyl and/or
secondary butyl groups derived from (D).
The amount of isopropyl or secondary butyl
groups deri~ed from (D) in the oil or to be added to the
oil can be calculated using the following formula:
wt % of iPr or s-butyl groups = wt % of P in oil x
2~43* or 57*) x mole % of iPr or s-butYl qrou~s in
31* 100
hydrocarbon mixture of (D)
*43 is formula weight of an isopropyl group.
*57 is formula weight of a secondary butyl group.
*31 is atomic weight of phosphorus.
~ The alcohol mixtures which are utilized in the
preparation of the phosphorodithioic acids of this last
embodiment comprise mixtures of isopropyl alcohol, secon-
dary butyl alcohol or a mixture of isopropyl and secon-
dary butyl alcohols, and at least one primary or alipha-
tic alcohol containing from about 5 to 13 carbon atoms.
In particular, the alcohol mixture will contain at least
20, 25 or 30 mole percent of isopropyl and/or secondary
butyl alcohol and will generally comprise from about 20
mole percent to about 90 mole percent of isopropyl or
secondary butyl alcohol. In one preferred embodiment,
the alcohol mixture will comprise from about 30 to about
~n~
-50-
mole percent of isopropyl alcohol, the remainder
being one or more primary aliphatic alcohols.
The primary alcohols which may be included in
the alcohol mixture include n-amyl alcohol, isoamyl alco-
hol, n-hexyl alcohol, 2-ethyl-1-hexyl alcohol, isooctyl
alcohol, nonyl alcohol, isodecyl alcohol, dodecyl alco-
hol, tridecyl alcohol, etc. The primary alcohols also
may contain various substituent groups such as halogens.
Particular examples of useful mixtures of alcohols
include, for example, isopropyl/2-ethyl-1-hexyl; isopro-
pyl/isooctyl; isopropyl/isodecyl; isopropyl/dodecyl; and
isopropyl/tridecyl. In one prefered embodiment, the pri-
mary alcohols will contain from 6 to 13 carbon atoms,
and the total number of carbon atoms per phosphorus atom
in the required phophorodithioic acid salt will be at
least 9.
The composition of the phosphorodithioic acid
obtained by the reaction of a mixture of alcohols (e.g.,
iPrOH and R20H) with phosphorus pentasulfide is actual-
ly a statistical mixture of phosphorodithioic acids as
illustrated by the following formulae:
iPrO ~ iPrO \
PSSH, PSSH; and
R20 / iPrO /
R20 ~
~ PSSH
R O
In the present invention it is preferred to select the
amount of the two or more alcohols reacted with P2S5
to result in a mixture in which the predominating dithio-
8~9
-51 -
phosphoric acid is the acid (or acids) containing one
isopropyl group or one secondary butyl group, and one
primary or secondary alkyl group containing at least 5
carbon atoms. The relative amounts of the three phos-
phorodithioic acids in the mixture is dependent, in
part, on the relative amounts of the alcohols in the
mixturer steric effects, etc.
The following Examples D-1 to D-6 illustrate
the preparation of metal phosphorodithioates prepared
from mixtures of alcohols.
Example D-1
A phosphorodithioic acid is prepared by react-
ing a mixture o alcohols comprising 6 moles of ~-meth-
yl-2-pentanol and ~ moles of isopropyl alcohol with phos-
phorus pentasulfide. The phosphorodithioic acid then is
reacted with an oil slurry of zinc oxide. The amount of
zinc oxide in the slurry is about 1.08 times the theore-
tical amount required to completely neutralize the
phosphorodithioic acid. The oil solution of the zinc
phosphorodithioate obtained in this manner (10% oil)
contains 9.5% phosphorus, 20.0% sulfur and 10.5% zinc.
Example D-2
~ A phosphorodithioic acid is prepared by react-
ing finely powdered phosphorus pentasulfide with an alco-
hol mixture containing 11.53 moles (692 parts by weight)
of isopropyl alcohol and 7.69 moles (1000 parts by
weight) of isooctanol. The phosphorodithioic acid
obtained in this manner has an acid number of about 178-
186 and contains 10.0% phosphorus and 21.0% sul~ur. This
phosphorodithioic acid is then reacted with an oil slur-
ry of zinc oxide. The quantity of zinc oxide included
in the oil slurry is 1.10 times the theoretical equiva-
lent of the acid number of the phosphorodithioic acid.
Z/~)17B~g
-52-
The oil solution of the zinc salt prepared in this man-
ner contains 12% oil, 8.6% phosphorus, 18.5% sulfur and
9~s% z.inc.
Example D-3
A phosphorodithioic acid is prepared by react-
ing a mixture of 1560 parts (12 moles) of isooctyl alco-
hol and 180 parts (3 moles) of isopropyl alcohol with
756 parts (3.4 moles) of phosphorus pentasulfide. The
reaction is conducted by heating the alcohol mixture to
about 55C and thereafter adding the phosphorus pentasul-
fide over a period of 1.5 hours while maintaining the
reaction temperature at about 60-75C. After all of the
phosphorus pentasulide is added, the mixture is heated
and stirred for an additional hour at 70-75C, and there-
after filtered through a filter aid.
Zinc oxide (282 parts, 6.87 moles) is charged
to a reactor with 278 parts of mineral oil. The above-
prepared phosphorodithioic acid (2305 parts, 6.28 moles)
is charged to the zinc oxide slurry over a period of 30
minutes with an exotherm to 60C. The mixture then is
heated to 80C and maintained at this temperature for 3
hours. After stripping to 100C and 6 mm.Hg., the mix-
ture is filtered twice through a filter aid, and the
filtrate is the desired oil solution of the zinc salt
containing 10~ oil, 7.97% zinc (theory 7.40~; 7.21% phos-
phorus (theory 7.06); and 15.64% sulfur (theory 14.57).
Example D-4
Isopropyl alcohol (396 parts, 6.6 moles) and
12B7 parts (9.9 moles) of isooctyl alcohol are charged
to a reactor and heated with stirring to 59C. Phos
phorus pentasulfide (833 parts, 3.75 moles) is then
added under a nitrogen sweep. The addition of the phos-
phorus pentasulfide is completed in about 2 hours at a
7~319
-53-
reaction temperature between 59-63C. The mixture then
is stirred at 45-63C for about 1.45 hours and filtered.
The filtrate is the desired phosphorodithioic acid.
A reactor is charged with 312 parts (7.7 equiva-
lents) of zinc oxide and 580 parts of mineral oil. While
stirring at room temperature, the above-prepared phos-
phorodithioic ac~d (2287 parts, 6.97 equivalents) is
added over a period of about 1.26 hours with an exotherm
to 54C. The mixture is heated to 78C and maintained
at 78-85C for 3 hours. The reaction mixture is vacuum
stripped to 100C at 19 mm.Hg. The residue is filtered
through a filter aid, and the filtrate is an oil solu-
tion (19.2% oil) of the desired zinc salt containing
7.86% zinc, 7.76% phosphorus and 14.8% sulfur.
Example D-5
The general procedure of Example D-4 is repeat-
ed except that the mole ratio of isopropyl alcohol to
isooct~l alcohol is 1:1. The product obtained in this
manner is an oil solution (10% oil) of the zinc phosphor-
odithioate containing 8.96% zinc, 8.49% phosphorus and
18.05% sulfur.
Example D-6
` A phosphorodithioic acid is prepared in accord-
ance with the general procedure of Example D-4 utilizing
an alcohol mixture containing 520 parts (4 moles) of
isooctyl alcohol and 360 parts (6 moles) of isopropyl
alcohol with 504 parts (2.27 moles) of phosphorus penta-
sulfide. The zinc salt is prepared by xeacting an oil
slurry of 116.3 parts of mineral oil and 141.5 parts
(3.44 moles) of zinc oxide with 950.8 parts (3.20 moles~
of the above-prepared phosphorodithioic acid. The prod-
uct prepared in this manner is an oil solution (10%
mineral oil) of the desired zinc salt, and the oil solu-
Z~317~
-54-
tion contains 9.36% zinc, 8.81% phosphorus and 18.65%
sulfur.
Additional specific examples of metal phosphoro-
dithioates useful as component (D) in the lubricating
oils of the present invention are listed in the follow-
ing table. Examples D-7 to D-11 are prepared from sin-
gle alcohols, and Examples D-12 to D-15 are prepared
from alcohol mixtures following the general procedure of
Example D-1.
TABLE I
Component D: Metal Phosphorodithioates
~R10 ~ ~
PSS~M
~R20 J
Example R1 ~ R2 M n
D-7 n-nonyl n-nonyl Ba 2
D-8 cyclohexyl cyclohexyl Zn 2
D-9 isobutyl isobutyl Zn 2
D-10 hexyl hexyl Ca 2
D-11 iso-decyl iso-decyl Zn 2
D-12 (n-butyl + dodecyl) (1:1 )w Zn 2
D-13 (isopropyl + isooctyl) (1:1~w Ba 2
D-14 (isobutyl + isoamyl) (65:35)m Zn 2
D-15 (isopropyl+sec-butyl~ (40:60)m Zn 2
Another class of the phosphorodithioate addi-
tives contemplated for use in the lubricating composi-
tion of this invention comprises the adducts of the
metal phosphorodithioates described above with an epox-
ide. The metal phosphorodithioates useful in preparing
such adducts are for the most part the ~inc phosphorodi-
L7~
thioates. The epoxides may be alkylene oxides or arylal-
~ylene oxides. The arylalkylene oxides are exemplified
by styrene oxide, p-ethylstyrene oxide, alpha-methylsty-
rene oxide, 3-beta-naphthyl-1,1,3-butylene oxide, m-dode-
cylstyrene oxide, and p-chlorostyrene oxide. The alkyl-
ene oxides include principally the lower alkylene oxides
in which the alkylene radical contains 8 or less carbon
atoms. Examples of such lower alkylene oxides are ethyl-
ene oxide, propylene oxide, 1,2-butene oxide, trimethyl-
ene oxide, tetramethylene oxide, butadiene monoepoxide,
1,2-hexene oxide, and epichlorohydrin. Other epoxides
useful herei~ in~lude, for example, butyl 9,10-epoxy-
stearate, epoxidized soya bean- oil, epoxidized tung oil,
and epoxidi~ed copolymer of styrene with butadiene.
The adduct may be obtained by simply mixing the
metal phosphorodithioate and the epoxide. The reaction
is usually exothermic and may be carried out within wide
temperature limits from about 0C to about 300C. Be-
cause the reaction is exothermic, it is best carried out
by addinq one reactant, usually the epoxide, in small
increments to the other reactant in order to obtain con-
venient control of the temperature of the reaction. The
rsaction may be carried out in a solvent such as ben-
zene, mineral oil, naphtha, or n-hexene.
The chemical structure o~ the adduct is not
known. For the purpose of this invention adducts obtain-
ed by the reartion of one mole o~ the phosphorodithioate
with from about 0.25 mole to 5 moles, usually up to
about 0.75 mole or about 0.5 mole of a lower alkylene
oxide, particularly ethylene oxide and propylene oxide,
have been found to be especially useful and therefore
are preferred.
~7~
-56-
The preparation of such adducts is more speci-
fically illustrated by the following examples.
Example D-16
A reactor is charged with 2365 parts (3.33
moles) of the zinc phosphorodithioate prepared in Exam-
ple D-2, and while stirring at room temperature, 38.6
parts (0.67 mole) of propylene oxide are added with an
exotherm of from 2~-31C. The mixture is maintained at
80-90C for 3 hours and then vacuum stripped to 101C at
7 mm. Hg. The residue is filtered using a filter aid,
and the ~iltrate is an oil solution (11.8% oil) of the
desired salt containing 17.1% sulfur, 8.17% zinc and
7.44% phosphorus.
Example D-17
To 394 parts (by weight) of zinc dioctylphos-
phorodithioate having a phosphorus content of 7% there
is added at 75-85C, 13 parts of propylene oxide (0.5
mole per mole of the zinc phosphorodithioate) throughout
a period of 20 minutes. The mixture is heated at 82-85C
for one hour and filtered. The filtrate (399 parts) is
found to contain 6.7~ of phosphorus, 7.4% of zinc, and
4.1% of sulfur.
~ Another class of the phosphorodithioate addi-
tives (D) contemplated as useful in the lubricating com-
positions of the invention comprises mixed metal salts
of (a) at least one phosphorodithioic acid of Formula
VIII as defined and exemplified above, and (b) at least
one aliphatic or alicyclic carboxylic acid. The carbox-
ylic acid may be a monocarboxylic or polycarboxylic
acid, usually containing from 1 to about 3 carboxy
~roups and preferably only 1. It may contain from about
2 to about 40, preferably from about 2 to about 20
carbon atoms, and advantageously about 5 to about 20
8~g
-57-
carbon atoms. The preferred carboxylic acids are those
having the formula R3CooH, wherein R3 is an alipha-
tic or alicyclic hydrocarbon-based radical preferably
free from acetylenic unsaturation. Suitable acids
include the butanoic, pentanoic, hexanoic, octanoic,
nonanoic, decanoic, dodecanoic, octadecanoic and eico-
sanoic acids, as well as olefinic acids such as oleic,
linoleic, and linolenic acids and linoleic acid dimer.
For the most part, R3 is a saturated aliphatic group
and especially a branched alkyl group such as the iso-
propyl or 3-heptyl group. Illustrative polycarboxylic
acids are succinic, alkyl- and alkenylsuccinic, adipic,
sebacic and citric acids. -
~
The mixed metal salts may be prepared by merelyblending a metal salt of a phosphorodithioic acid with a
metal salt of a carboxylic acid in the desired ratio.
The ratio of equivalents of phosphorodithioic to carbox-
ylic acid salts is between about 0.5:1 to about 400:1.
Preferably, the ratio is between about 0.5:1 and about
200:1. Advantageously, the ratio can be from about
0.5:1 to about 100:1, preferably from about 0.5:1 to
about 50:1, and more preferably from about 0.5:1 to
about 20:1. Further, the ratio can be from about 0.5:1
to about 4.5:1, preferably about 2.5:1 to about 4.25:1.
For this purpose, the equivalent weight of a phosphoro-
dithioic acid is its molecular weight divided by the
number of -PSSH groups therein, and that of a carboxylic
acid is its molecular weight divided by the number of
carboxy groups therein.
A second and preferred method for preparing the
mixed metal salts useful in this invention is to prepare
a mixture of the acids in the desired ratio and to react
the acid mixture with a suitable metal base. ~hen this
2n~7~
-58-
method of preparation is used, it is frequently possible
to prepare a salt containing an excess of metal with
respect to the number of equivalents of acid present;
thus, mixed metal salts containing as many as 2 equiva-
lents and especially up to about 1.5 equivalents of
metal per equivalent of acid may be prepared. The equiv-
alent of a metal for this purpose is its atomic weight
divided by its Yalence.
Variants of the above-described methods may
also be used to prepare the mixed metal salts useful in
this invention. For example, a metal salt of either
acid may be blended with an acid of the other, and the
resulting blend reacted with additional metal base.
Suitable metal bases for the preparation of the
mixed metal salts include the free metals previously
enumerated and their oxides, hydroxides, alkoxides and
basic salts. Examples are sodium hydroxide, potassium
hydroxide, magnesium oxide, calcium hydroxide, zinc
oxide, lead oxide, nickel oxide and the like.
The temperature at which the mixed metal salts
are prepared is generally between about 30C and about
150C, preferably up to about 125C. If the mixed salts
are prepared by neutralization of a mixture of acids
with a metal base, it is preferred to employ tempera-
tures above about 50C and especially above about 75C.
It is frequently advantageous to conduct the reaction in
the presence of a substantially inert, normally liquid
organic diluent such as naphtha, benzene, xylene, miner-
al oil or the like. If the diluent is mineral oil or is
physically and chemically similar to mineral oil, it
frequently need not be removed before using the mixed
metal salt as an additive for lubricants or functional
fluids.
L7~
-59-
U.S. Patents 4,308,154 and 4,417,990 describe
procedures for preparing these mixed metal salts and
disclose a number of examples of such mixed salts. Such
disclosures of these patents are hereby incorporated by
reference.
The preparation of the mixed salts is illustrat-
ed by the following examples.
Example D-18
A mixture of 67 parts (1.63 equivalents) of
zinc oxide and 48 parts of mineral oil is stirred at
room temperature and a mixture of 401 parts (1 equiva-
lent) of di-(2-ethylhexyl) phosphorodithioic acid and 36
parts (0.25 equivalent) of 2-ethylhexanoic acid is added
over 10 ~inutes. The temperature increases to 40C
during the addition. When addition is complete, the
temperature is increased to 80C for 3 hours. The
mixture is then vacuum stripped at l00C to yield the
desired mixed metal salt as a 91% solution in mineral
oil.
Example D-19
Following the procedure of Example D-18, a
product is prepared from 383 parts (1.2 equivalents) of
a dialkyl phosphorodithioic acid containing 65~ isobutyl
and 35~ amyl groups, 43 parts (0.3 equivalent~ of 2-eth-
ylhexanoic acid, 71 parts (1.73 equivalents) of zinc
oxide and 47 parts of mineral oil. The resulting mixed
metal salt, sbtained as a 90% solutisn in mineral oil,
contains 11 . 07% zinc.
(E) Neutral or Basic Alkali Metal Salt.
The lubricating oil compositions of this inven-
tion also may contain at least one neutral or basic
alkali metal salt of at least one sulfonic or carboxylic
acid. The amount of alkali metal salt in the lubricat-
~:~3~7~9
-60-
ing oil is an amount which is effective to provide the
desired detergent properties to the oil. Generally, the
lubricants will contain from about 0.01~ to about 5% of
the alkali metal salt, and more often from about 0.01%
to about 3~. A general description of some of the
alkali metal salts useful as component tE) is contained
in U.S. Patent 4,326,972 (Chamberlin). This patent is
hereby incorporated by reference for its disclosure of
useful alkali metal salts and methods for preparing said
salts.
The alkali metals present in the basic alkali
metal salts include principally lithium, sodium and
potassium, with sodium and potassium being preferred.
The equivalent weight of the acidic organic
compound is its molecular weight divided by the number
of acidic groups (i.e., sulfonic acid or carboxy groups)
present per molecule.
In one preferred embodiment, the alkali metal
salts (E) are basic alkali metal salts having metal
ratios of at least about 2 and more generally from about
4 to about 40, preferably from about 6 to about 30 and
especially from about 8 to about 25.
~ The acidic organic compound from which the salt
of component (E) is derived may be at least one sulfur
acid, carboxylic acid, phosphorus acid, or phenol or
mixtures thereof. The sulfur acids include the sulfonic
acids, thiosulfonic, sulfinic, sulfenic, partial ester
sulfuric, sulfuxous and thiosulfuric acids.
The sulfonic acids which are useful in prepar-
ing component (E) include those represented ~y the formu-
lae
~ 78~9
-61-
RXT(SO3H)y (IX)
and
R'(SO3H)r (X)
In these formulae, R' is an aliphatic or aliphatic-sub-
stituted cycloaliphatic hydrocarbon or essentially hydro-
carbon group free from acetylenic unsaturation and con-
taining up to about 60 carbon atoms. When R' is alipha-
tic, it usually contains at least about 15 carbon atoms;
when it is an aliphatic-substituted cycloaliphatic
group, the aliphatic substituents usually contain a
total of at least about 12 carbon atoms. Exam~les of R'
are alkyl, alkenyl and alkoxyalkyl radicals, and alipha-
tic-substituted cycloaliphatic groups wherein the alipha-
tic substituents are alkyl, alkenyl, alkoxy, alkoxy-
alkyl, carboxyalkyl and the like. Generally, the cyclo-
aliphatic nucleus is derived from a cycloalkane or a
cycloalkene such as cyclopentane, cyclohexane, cyclohex-
ene or cyclopentene. Specific examples of R' are cetyl-
cyclohexyl, laurylcyclohexyl, cetyloxyethyl, octadec-
enyl, and groups derived from petroleum, saturated and
unsaturated paraffin wax, and olefin polymers including
polymerized monoolefins containing about 2-8 carbon
atoms per olefinic monomer unit and dioiefins containinq
4 to 8 carbon atoms per monomer unit. R' can also
contain other substituents such as phenyl, cycloalkyl,
hydroxy, mercapto, halo, nitro, amino, nitroso, lower
alkoxy, lower alkylmercapto, carboxy, carbalkoxy, oxo or
thio, or interrupting groups such as -NH-, -O- or -S-,
as long as the essentially hydrocarbon character is not
destroyed.
~7~
-62-
R in Formula IX is generally a hydrocarbon or
essentially hydrocarbon group free from acetylenic unsat-
uration and containing from about 4 to about 60 alipha-
tic carbon atoms, preferably an aliphatic hydrocarbon
group such as alkyl or alkenyl. It may also, however,
contain substituents or interrupting groups such as
those enumerated above provided the essentially hydro-
carbon character thereof is retained. In general, any
non-carbon atoms present in R' or R do not account for
more than 10% of the total weight thereof.
T is a cyclic nucleus which may be derived from
an aromatic hydrocarbon such as benzene, naphthalene,
anthracene or biphenyl, or from a heterocyclic compound
such as pyridine, indole or isoindole. Ordinarily, T is
an aromatic hydrocarbon nucleus, especially a benzene or
naphthalene nucleus.
The subscript x is at least 1 and is generally
1~3. The subscripts r and y have an average value of
about 1-2 per molecule and are generally also 1.
The sulfonic acids are generally petroleum sul-
fonic acids or synthetically prepared alkaryl sulfonic
acids. Among the petroleum sulfonic acids, the most
useful products are those prepared by the sulfonation of
suitable petroleum fractions with a subsequent removal
of acid sludge, and purification. Synthetic alkaryl
sulfonic acids are prepared usually from alkylated ben-
zenes such as the Friedel-Crafts reaction products of
benzene and polymers such as tetrapropylene. The follow-
ing are specific examples of sulfonic acids useful in
preparing the salts (E). It is to be understood that
such examples serve also to illustrate the salts of such
sulfonic acids useful as component ~). In other words,
for every sulfonic acid enumerated, it is intended that
Zr317~ 9
,,
-63-
the corresponding basic alkali metal salts thereof are
also understood to be illustrated. (The same applies to
the lists of other acid materials listed below.) Such
sulfonic acids include mahogany sulfonic acids, bright
stock sulfonic acids, petrolatum sulfonic acids, mono-
and polywax substituted naphthalene sulfonic acids,
cetylchlorobenzene sulfonic acids, cetylphenol sulfonic
acids, cetylphenol disulfide sulfonic acids, cetoxy-
capryl benzene sulfonic acids, dicetyl thianthrene sul-
fonic acids, dilauryl beta-naphthol sulfonic acids, di-
capryl nitronaphthalene sulfonic acids, saturated paraf-
fin wax sulfonic acids, unsaturated paraffin wax sulfon-
ic acids, hydroxy-substituted paraffin wax sulfonic
acids, tetraisobutylene sulfonic acids, tetraamylene
sulfonic acids, chlorine substituted paraffin wax sul-
fonic acids, nitroso substituted paraffin wax sulfonic
acids, petroleum ~aphthene sulfonic acids, cetylcyclo-
pentyl sulfonic acids, lauryl cyclohexyl sulfonic acids,
mono- and polywax substituted cyclohexyl sulfonic acids,
dodecylbenzene sulfonic acids, "dimer alkylate" sulfonic
acids, and the like.
Alkyl-substituted benzene sulfonic acids where-
in the alkyl group contains at least 8 carbon atoms
including dodecyi benzene "bottoms" sulfonic acids are
pa~ticularly useful. The latter are acids derived from
benzene which has been alkylated with propylene tetra-
mers or isobutene trimers to introduce 1, 2, 3, or more
branched-chain C12 substituents on the benzene ring.
Dodecyl benzene bottoms, principally mixtures of mono-
and di-dodecyl benzenes, are available as by products
from the manufacture of household detergents. Similar
products obtained from alkylation bottoms formed during
manufacture of linear alkyl sulfonates (LAS) are also
useful in making the sulfonates used in this invention.
2')~78~
-64-
The production of sulfonates from detergent
manufacture by-products by reaction with, e.g., SO3,
is well known to those skilled in the art. See, for
example, the article "Sulfonates" in Kirk-Othmer "Ency-
clopedia of Chemical Technology", Second Edition, Vol.
19, pp. 291 et seq. published by John Wiley & Sons, N.Y.
(1969).
Other descriptions of basic sulfonate salts
which can be incorporated into the lubricating oil compo-
sitions of this invention as component (E), and techni-
ques for making them can be found in the following U.S.
Patents: 2,17~,110; 2,202,781; 2,239,974; 2,319,121;
2,337,552; 3,488,284; 3,595,790; and 3,798,012. These
are hereby incorporated by reference for their disclo-
sures in this regard.
Suitable carboxylic acids from which useful
alkaline earth metal salts (E) can be prepared include
aliphatic, cycloaliphatic and aromatic mono- and poly-
basic carboxylic acids including naphthenic acids,
alkyl- or alkenyl-substituted cyclopentanoic acids,
alkyl- or alkenyl-substituted cyclohexanoic acids, and
alkyl- or alkenyl-substituted aromatic carboxylic acids.
~he aliphatic acids generally contain from about 8 to
about 50, and preferably from about 12 to about 25
carbon atoms. The cycloaliphatic and aliphatic carbox-
ylic acids are preferred, and they can be saturated or
unsaturated. Specific examples include ~-ethylhexanoic
acid, linolenic acid, propylene tetramer-substituted
maleic acid, behenic acid, isostearic acid, pelargonic
acid, capric acid, palmitoleic acid, linoleic acid,
lauric acid, oleic acid, ricinoleic acid, undecyclic
acid, dioctylcyclopentanecarboxylic acid, myristic acid,
dilauryldecahydronaphthalene-carboxylic acid, stearyl-
Z~ B~.9
-65-
octahydroindenecarboxylic acid, palmitic acid, alkyl-
and alkenylsuccinic acids, acids formed by oxidation of
petrolatum or of hydrocarbon waxes, and commercially
available mixtures of two or more carboxylic acids such
as tall oil acids, rosin acids, and the like.
In one preferred embodiment, the basic sulfon-
ate salts (E) are oil-soluble dispersions prepared by
contacting for a period of time sufficient to form a
stable dispersion, at a temperature between the solidifi-
cation temperature of the reaction mixture and its decom-
position temperature:
(E-1) at least one acidic gaseous material
selected from the group consisting of carbon dioxide,
hydrogen sulfide and sulfur dioxide, with
~ E-2) a reaction mixture comprising
(E-2-a) at least one oil-soluble sulfon-
ic acid, or derivative thereof susceptible to overbas-
ing;
(E-2-b) at least one alkali metal or
basic alkali metal compound;
(E-2-c) at least one lower aliphatic
alcohol, alkyl phenol, or sulfurized alkyl phenol; and
~ (E-2-d) at least one oil-soluble carbox-
ylic acid or functional derivatiYe thereof.
When (E-2-c) is an alkyl phenol or a sulfurized
alkyl phenol, component (E-2-d) is optional. A satis-
~actory basic sulfonic acid salt can be prepared with or
without the carboxylic acid in the mixture (E-2).
Reagent (E-1) is at least one acidic gaseous
material which may be carbon dioxide, hydrogen sulfide
or sulfur dioxide; mixtures of these gases are also
useful. Carbon dioxide is preferred.
Zf~83~
-66-
~ s mentioned above, component (E-2) generally
is a mixture containing at least four components of
which component ~E-2-a) is at least one oil-soluble sul-
fonic acid as previously defined, or a derivative there-
of susceptible to overbasing. Mixtures of sulfonic
acids and/or their derivatives may also be used. Sul~on-
ic acid derivatives susceptible to overbasing include
their metal salts, especially the alkaline earth, zinc
and lead salts; ammonium salts and amine salts (e.g.,
the ethylamine, butylamine and ethylene polyamine
salts); and esters such as the ethyl, butyl and glycerol
esters.
Component (E-2-b) is preferably and generally
is at least one basic alkali metal compound. Illustra-
tive of basic alkali metal compounds are the hydroxides,
alkoxides (typically those in which the alkoxy group
contains up to 10 and preferably up to 7 carbon atoms),
hydrides and amides. Thus, useful basic alkali metal
compounds include sodium hydroxide, potassium hydroxide,
lithium hydroxide, sodium propoxide, lithium methoxide,
potassium ethoxide, sodium butoxide, lithium hydride,
sodium hydride, potassium hydride, lithium amide, sodium
amide and potassium amide. Especially preferred are
sodium hydroxide and the sodium lower alkoxides (i.e.,
those containing up to 7 carbon atoms). The equivalent
weight of component (E-2-b) for the purpose of this
invention is equal to its molecular weight, since the
alkali metals are monovalent.
Component (E-2-c) may be at least one lower
aliphatic alcohol, preferably a monohydric or dihydric
alcohol. Illustrative alcohols are methanol, ethanol,
1-propanol, 1-hexanol, isopropanol, isobutanol, 2-pen-
tanol, 2,2-dimethyl-1-propanol, ethylene glycol, 1-3-pro-
~78~
-67-
panediol and 1,5-pentanediol. The alcohol also may be a
glycol ether such as Methyl Cellosolve. o~ these, the
preferred alcohols are methanol, ethanol and propanol,
with methanol being especially preferred.
Component (E-2-c) also may be at least one
alkyl phenol or sulfurized alkyl phenol. The sulfurized
alkyl phenols are preferred, especially when (E-2-b) is
potassium or one of its basic compounds such as potas-
sium hydroxide. As used herein, the term "phenol"
includes compounds having more than one hydroxy group
bound to an aromatic ring, and the aromatic rin~ may be
a benzyl or naphthyl ring. The term "alkyl phenol"
includes mono- and di-alkylated phenols in which each
alkyl substituent contains from about 6 to about 100
carbon atoms, preferably about 6 to about 50 carbon
atoms.
Illustrative alkyl phenols include heptyl-
phenols, octylphenols, decylphenols, dodecylphenols,
polypropylene (Mn of about 150)-substituted phenols,
polyisobutene (Mn of about 1200)-substituted phenols,
cyclohexyl phenols.
Also useful are condensation products of the
above-described phenols with at least one lower aldehyde
or ketone, the term "lower" denoting aldehydes and ke-
tones containing not more than 7 carbon atoms. Suitable
aldehydes include formaldehyde, acetaldehyde, propional-
dehyde, the butyraldehydes, the valeraldehydes and ben~-
aldehyde. Also suitable are aldehyde-yielding reagents
such as paraformaldehyde, trioxane, methylol, Methyl
Formcel and paraldehyde. Formaldehyde and the formalde-
hyde-yielding reagents are especially preferred.
The sulfurized alkylphenols include phenol sul-
fides, disulfides or polysulfides. The sulfurized phen-
8~
-68-
ols can be derived from any suitable alkylphenol by tech-
nique known to those skilled in the art, and many sulfur-
ized phenols are commercially available. The sulfurized
alkylphenols may be prepared by reacting an alkylphenol
with elemental sulfur and/or a sulfur monohalide (e.g.,
sulfur monochloride). This reaction may be conducted in
the presence of excess base to result in the salts of
the mixture of sulfides, disulfides or poly sulfides
that may be produced depending upon the reaction condi-
tions. It is the resulting product of this reaction
which is used in the preparation of component (E-2) in
the present inventior.. U.S. Patents 2,971,940 and
4,309,293 disclose various sulfurized phenols which are
illustrative of component (~-2-c), and such disclosures
of these patents are hereby incorporated by reference.
The equivalent weight of component (E-2-c) is
its molecular wei~ht divided by the number of hydroxy
groups per molecule.
Component (E-2-d3 is at least one oil-soluble
carboxylic acid as previously described, or functional
derivative thereof. Especially suitable carboxylic
acids are those of the formula R5(cooH)nl wherein n
is an integer from 1 to 6 and is preferably 1 or 2 and
R5 is a saturated or ~ubstantially saturated aliphatic
group (pre~erably a hydrocarbon group) having at least 8
aliphatic carbon atoms. Depending upon the value of n,
R5 will be a monovalent to hexavalent radical.
R5 may contain non-hydrocarbon substituents
provided they do not alter substantially its hydrocarbon
character. Such substituents are preferably present in
amounts of not more than about 20% by weight. Exemplary
substituents include the non-hydrocarbon substituents
enumerated hereinabove with reference to component (E-2-
ZS)~8~9
-69-
a). R5 may also contain olefinic unsaturation up to a
maximum of about 5% and preferably not more than 2% ole-
finic linkages based upon the total number of carbon-
to-carbon covalent linkages present~ The number of car-
bon atoms in R5 is usually about 8-700 depending upon
the source of R5. As discussed below, a preferred
series of carboxylic acids and derivatives is prepared
by reacting an olefin polymer or halogenated olefin
polymer with an alpha, beta-unsaturated acid or its anhy-
dride such as acrylic, methacrylic, maleic or fumaric
acid or maleic anhydride to form the corresponding sub-
stituted acid or derivative thereof. The R5 groups in
these products have a number average molecular weight
from about 150 to about 10,000 and usually from about
700 to about 5000, as determined, for example, by gel
permeation chromatography.
The monocarboxylic acids useful as component
(E-2-d) have the formula R5CooH. Examples of such
acids are caprylic, capric, palmitic, stearic, isostear-
ic, linoleic and behenic acids. A particularly prefer-
red group of monocarboxylic acids is prepared by the
reaction of a halogenated olefin polymer, such as a
~hlorinated polybutene, with acrylic acid or methacrylic
acid.
Suitable dicarboxylic acids include the substi-
tuted succinic acids haYing the formula
R6CHCOOH
CH2COOH
wherein R6 is the same as R5 as defined above. R6
may be an olefin polymer-derived group formed by polymer-
ization of such monomers as ethylene, propylene, 1-bu-
Z0~7~
-70-
tene, isobutene, 1-pentene, 2-pentene, 1-hexene and 3-
hexene. ~6 may also be derived from a high molecular
weight substantially saturated petroleum fraction. The
hydrocarbon-substituted succinic acids and their deriva-
tives constitute the most preferred class of carboxylic
acids for use as component (E-2-d).
The above-described classes of carboxylic acids
derived from olefin polymers, and their derivatives, are
well known in the art, and methods for their preparation
as well as representative examples of the types useful
in the present invention are described in detail in a
number of U.S. Patents.
Functional derivatives of the above-discussed
acids useful as component (E-2-d) include the anhy-
drides, esters, amides, imides, amidines and metal or
ammonium salts. The reaction products of olefin poly-
mer-substituted succinic acids and mono or polyamines,
particularly polyalkylene polyamines, having up to about
amino nitro~ens are especially suitable. These reac-
tion products generally comprise mixtures of one or more
of amides, imides and amidines. The reaction products
of polyethylene amines containing up to about 10 nitro-
gen atoms and polybutene substituted succinic anhydride
wherein the polybutene radical comprises principally
isobutene units are particularly useful. Included in
this group of functional derivatives are the composi-
tions prepared by post treating the amine-anhydride
reaction product with carbon disulfide, boron compounds,
nitriles, urea, thiourea, guanidine, alkylene oxides or
the like. The half-amide, half-metal salt and half-
ester, half-metal salt derivatives of such substituted
succinic acids are also useful~
;~3~78~3
-71-
Also useful are the esters prepared by the reac-
tion of the substituted acids or anhydrides with a mono
or polyhydroxy compound, such as an aliphatic alcohol or
a phenol. Preferred are the esters of olefin polymer-
substituted succinic acids or anhydrides and polyhydric
aliphatic alcohols containing 2-10 hydroxy groups and up
to about 40 aliphatic carbon atoms. This class of alco-
hols includes ethylene glycol, glycerol, sorbitol, pen-
taerythritol, polyethylene glycol, diethanolamine, tri-
ethanolamine, N,N'-dithydroxyethyl)ethylenediamine and
the like. When the alcohol contains reactive amino
groups, the reaction product may comprise products
resulting from the reaction of the acid group with both
the hydroxy and amino functions. Thus, this reaction
mixture can include half-esters, half-amides, esters,
amides, and imides.
The ratios of equivalents of the constituents
of reagent (E-2) may vary widely. In general, the ratio
of component (E-2-b) to (E-2-a) is at least about 4:1
and usually not more than about 40:l, preferably between
6:1 and 30:1 and most preferably between 8:1 and 25:1.
While this ratio may sometimes exceed 40:1, such an
excess normally will serve no useful purpose.
The ratio of equivalents of component (E-2-c)
to component (E-2-a) is between about 1:20 and 80:1, and
preferably between about 2:1 and 50:1. As mentioned
above, when component (E-2-c) is an alkyl phenol or sul-
furized alkyl phenol, the inclusion of the carboxylic
acid (E-2-d~ is optional. When present in the mixture,
the ratio of equivalents of component (E-2-d) to compo-
nent (E-2-a) generally is from about 1:1 to about 1:20
and preferably from about 1:2 to about 1:10.
78~
-72~
Up to about a stoichiometric amount o~ acidic
material (E-1) is reacted with ~E-2). In one embodiment,
the acidic material is metered into the (E-2) mixture
and the reaction is rapid. The rate of addition of (E-1)
is not critical, but may have to be reduced if the temp-
erature of the mixture rises too rapidly due to the
exothermicity of the reaction.
When tE-2-c) is an alcohol, the reaction temp-
erature is not critical. Generally, it will be between
the solidification temperature of the reaction mixture
and its decomposition temperature (i.e., the lowest
decomposition temperature of any component thereo~).
Usually, the temperature will be from about 25C to
about 200C and preferably from about 50C to about
150C. Reagents (E-1) and (E-2) are conYeniently con-
tacted at the reflux temperature of the mixture. This
temperature will obviously depend upon the boiling
points of the various components; thus, when methanol is
used as component (E-2-c), the contact temperature will
be at or below the reflux temperature of methanol.
When reagent tE-2-c) is an alkyl phenol or a
sulfurized alkyl phenol, the temperature of the reaction
must be at or above the water azeotrope temperature so
that the water formed in the reaction can be removed.
The reaction is ordinarily conducted at atmos-
pheric pressure, although superatmospheric pressure
often expedites the reaction and promotes optimum util-
ization of reagent (E-1). The reaction also can be
carried out at reduced pressures but, for obvious prac-
tical reasons, this is rarely done.
The reaction is usually conducted in the pres-
ence of a substantially inert, normally liquid organic
diluent, which functions as both the dispersing and
Z~
-73-
reaction medium. This diluent will comprise at least
about 10% of the total weight of the reaction mixture.
~ pon completion of the reaction, any solids in
the mixture are preferably removed by filtration or
other conventional means. Optionally, readily removable
diluents, the alcoholic promoters, and water formed dur-
.ing the reaction can be removed by conventional techni-
ques such as distillation. It is usually desirable to
remove substantially all water from the reaction mixture
since the presence of water may lead to difficulties in
filtration and to the ~ormation of undesirable emulsions
in fuels and lubricants. Any such water present is read-
ily removed by heating at atmospheric or reduced pres-
sure or by azeotropic distillation. In one pre~erred
embodiment, when basic potassium sulfonates are desired
as component (E), the potassium salt is prepared using
carbon dioxide and the sulfurized alkylphenols as com-
ponent (E-2-C). The use of the sulfurized phenols
results in basic salts of higher metal ratios and the
formation of more uniform and stable salts.
The basic salts or complexes of component (E)
may be solutions or, more likely, stable dispersions.
Alternatively, they may be regarded as "polymeric salts"
formed by the reaction of the acidic material, the oil-
soluble acid being overbased, and the metal compound.
~n view of the above, these compositions are most con-
veniently defined by reference to the method by which
they are formed.
The above-described procedure for preparing
alkali metal salts of sulfonic acids havin~ a metal
ratio of at least about 2 and preferably a metal ratio
between about 4 to 40 using alcohols as component
(E-2-c) is described in more detail in Canadian Patent
2~
-74-
1,055,700 which corresponds to British Patent 1,481,553.
These patents are incorporated by reference for their
disclosures of such processes. The preparation of oil-
soluble dispersions of alkali metal sulfonates useful as
component (E) in the lubricating oil compositions of
this invention is illustrated further in the following
examples.
Example E-1
To a solution of 790 parts (1 equivalent) of an
alkylated benzenesulfonic acid and 71 parts of polybu-
tenyl succinic anhydride (equivalent weight about 560)
containing predominantly isobutene units in 176 parts of
mineral oil is added 320 parts-(8 equivalents) of sodium
hydroxide and 640 parts (20 equivalents) of methanol.
The temperature of the mixture increases to 89C (re-
flux) over 10 minutes due to exotherming. During this
period, the mixture is blown with carbon dioxide at 4
cfh. (cubic feet/hr.). Carbonation is continued for
about 30 minutes as the temperature gradually decreases
to 74C. The methanol and other volatile materials are
stripped from the carbonated mixture by blowing nitrogen
through it at 2 cfh. while the temperature is slowly
increased to 150C over 90 minutes. After stripping is
completed, the remaining mixture is held at 155-165C
for about 30 minutes and filtered to yield an oil solu-
tion of the desired basic sodium sulfonate having a
metal ratio of about 7.75. This solution contains 12.4%
oil.
Example E-2
Following the ~rocedure of Example E-1, a solu-
tion of 780 parts (1 equivalent) of an alkylated benzene-
sulfonic acid and 119 parts of the polybutenyl succinic
anhydride in 442 parts of mineral oil is mixed with 800
2~'~7~9
-75-
parts (20 equivalents3 of sodium hydroxide and 704 parts
(22 equivalents) of methanol. The mixture is blown with
carbon dioxide at 7 cfh. for 11 minutes as the tempera-
ture slowly increases to 97C. The rate of carbon diox-
ide flow is reduced to 6 cfh. and the temperature de-
creases slowly to 88C over about 40 minutes. The rate
of carbon dioxide flow is reduced to 5 cfh. for about 35
minutes and the temperature slowly decreases to 73C.
The volatile materials are stripped by blowing nitrogen
through the carbonated mixture at 2 cfh. for 105 minutes
as the temperature is slowly increased to 160C. After
stripping is completed, the mixture is held at 160C for
an additional 45 minutes and then filtered to yield an
oil solution of the desired basic sodium sulfonate hav-
ing a metal ratio of about 19.75. This solution contains
18.7% oil.
(F) CarboxYlic Ester Derivative Compositions.
The lubricating oil compositions of the present
invention also may, and often do contain (F) at least
one carboxylic ester derivative composition produced by
reacting (F-1) at least one substituted succinic acylat-
ing agent with (F-2) at least one alcohol or phenol of
the general formula
R3(~m (XI)
wherein R3 is a monovalent or polyvalent organic group
joined to the -OH ~roups through a carbon bond, and m is
an integer of from 1 to about 10. The ~arboxylic ester
derivatives (F) are included in the oil compositions in
amounts o~ up to about 10% by weight and more generally
in amounts of from about 1% to about 10~ by weight based
on the weight of the total lubricating oil. The carbox-
2n~
ylic esters (F) provide additional dispersancy, and insome applications, the ratio of carboxylic derivative
(B) to carboxylic ester (F) present in the oil affects
the properties of the oil compositions such as the
anti wear properties. The amount of carboxylic ester
derivative (F) contained in the lubricating oil composi-
tion may vary from about 0.1~ to about 10% by weight.
The substituted succinic acylating agents (F-1)
which are reacted with the alcohols or phenols to form
the carboxylic ester derivatives are identical to the
acylating agents (B-1) useful in preparing the carbox-
ylic derivati~es (B) described above with one exception.
The polyalkene from which the~substituent is derived is
characterized as having a number average molecular
weight of at least about 700.
Molecular weights (Mn) of from about 700 to
about 5000 are preferred. In one preferred embodiment,
the substituent groups of the acylating agent are deriv-
ed from polyalkenes which are characterized by an Mn
value of about 1300 to 5000 and an Mw/Mn value of about
1.5 to about 4.5. The acylating agents of this embodi-
ment are identical to the acylating agents described ear-
lier with respect to the preparation of the carboxylic
derivative compositions useful as component ~B) describ-
ed above. Thus, any of the acylating agents described
in regard to the preparation of component (B) above, can
be utilized in the preparation of the carboxylic ester
derivative compositions useful as component (F). When
the acylating agents used to prepare the carboxylic
ester (F) are the same as those acylating a~ents used
fox preparing component (B), the carboxylic ester compon-
ent (F) will also be characteriæed as a dispersant hav-
ing VI properties. Also combinations of component (B)
7~. 9
and these preferred types of component (F) used in the
oils of the invention provide superior anti-wear charac-
teristics to the oils of the invention. However, other
substituted succinic acylating agents also can be util-
ized in the preparation of the carboxylic ester deriva-
tive compositions which are useful as component ~F) in
the present invention. For example, substituted succin-
ic acylating agents wherein the substituent is derived
from a polyalkene having number average molecular
weights of about 800 to about 1200 are useful.
The carboxylic ester derivative compositions
(F) are those of the above-described succinic acylating
agents with hydroxy compounds which may be aliphatic
compounds such as monohydric and polyhydric alcohols or
aromatic ~ompounds such as phenols and naphthols. The
aromatic hydroxy compounds from which the esters may be
derived are illustrated by the following specific exam-
ples: phenol, beta-naphthol, alpha naphthol, cresol,
resorcinol, catechol, p,p'-dihydroxybiphenyl, 2-chloro-
phenol, 2,4-dibutylphenol, etc.
The alcohols ~F-2) from which the esters may be
derived preferably contain up to about 40 aliphatic
carbon atoms. They may be monohydric alcohols such as
methanol, ethanol, isooctanol, dodecanol, cyclohexanol,
etc. The polyhydric alcohols preferably contain from 2
to about 10 hydroxy groups. They are illustrated by,
for example, ethylene glycol, diethylene glycol, trieth-
ylene glycol, tetraethylene glycol, dipropylene glycol,
tripropylene glycol, dibutylene glycol, tributylene
glycol, and other alkylene glycols in which the alkylene
group contains from 2 to about 8 carbon atoms.
An especially preferred class of polyhydric
alcohols is those having at least three hydroxy groups,
7~319
-78-
some of which have been esterified with a monocarboxylic
acid having from about 8 to about 30 carbon atoms such
as octanoic acid, oleic acid, stearic acid, linoleic
acid, dodecanoic acid, or tall oil acid. Examples of
such partially esterified polyhydric alcohols are the
monooleate of sorbitol, distearate of sorbitol, mono-
oleate of glycerol, monostearate of glycerol, di-dodecan-
oate of erythritol.
The esters (F) may be prepared by any of sever-
al known methods. The method which is preferred because
o convenience and the superior properties of the esters
it produces, involves the reaction of a suitable alcohol
or phenol with a substantially hydrocarbon~substituted
succinic anhydride. The esterification is usually
carried out at a temperature above about 100C, prefer-
ably between 150C and 300C. The water formed as a by-
product is removed by distillation as the esterification
proceeds.
The relative proportions of the succinic react-
ant and the hydroxy reactant which are to be used depend
to a large measure upon the type of the product desired
and the number of hydro~yl groups present in the mole-
cule of the hydroxy reactant. For instance, the forma-
tion of a half ester of a succinic acid, i.e., one in
which only one of the two acid groups is esterified,
involves the use of one mole of a monohydric alcohol for
each mole of the substituted succinic acid reactant,
whereas the formation of a diester of a succinic acid
involves the use of two moles of the alcohol fo~ each
mole of the acid. On the other hand, one mole of a hexa-
hydric alcohol may combine with as many as six moles of
a succinic acid to form an ester in which each of the
six hydroxyl groups of the alcohol is esterified with
Z~!1'7~319
--79--
one of the two acid groups of the succinic acid. Thus,
the maximum proportion of the succinic acid to be used
with a polyhydric alcohol is determined by the number of
hydroxyl groups present in the molecule of the hydroxy
reactant. In one embodiment, esters obtained by the
reaction of equimolar amounts of the succinic acid react-
ant and hydroxy reactant are preferred.
Methods of preparing the carboxylic esters (F)
are well known in the art and need not be illustratPd in
further detail here. For example, see U.S. Patent
3,522,179 which is hereby incorporated by reference for
its disclosures of the preparation of carboxylic ester
compositions useful as component (F). The preparation
of carboxylic ester derivative compositions from acylat-
ing agents wherein the substituent groups are derived
from polyalkenes characterized by an ~n of at least
about 1300 up to about 5000 and an Mw/Mn ratio of from
1.5 to about 4 is described in U.S. Patent 4,234,435
which was incorporated by reference earlier. As noted
above, the acylating agents described in the '435 patent
are also characterized as havinq within their structure
an average of at least 1.3 succinic groups for each
equivalent wPight of substituent groups.
The following examples illustrate the esters
(F) and the processes for preparing such esters.
Example F-1
A substantially hydrocarbon-substituted succin-
ic anhydride is prepared by chlorinating a polyisobutene
having a number average molecular weight of 1000 to a
chlorine content of 4.5~ and then heating the chlorin-
ated polyisobutene with 1.2 molar proportions of maleic
anhydride at a temperature of 150-220C. The succinic
anhydride thus obtained has an acid number of 130. A
~f}~7~3~9
-80-
mixture of 874 grams (1 mole) of the succinic anhydride
and 104 grams (1 mole) of neopentyl glycol is maintained
at 240-250~C/30 mm for 12 hours. The residue is a
mixture of the esters resulting from the esterification
of one and both hydroxy groups of the glycol. It has a
saponification number of 101 and an alcoholic hydroxyl
content of 0.2%.
Example F-2
The dimethyl ester of the substantially hydro-
carbon-substituted succinic anhydride of Example F-1 is
prepared by heating a mixture of 2185 grams of the anhy-
dride, 480 grams of methanol, and 1000 cc of toluene at
50-65C while hydrogen chloride is bubbled through the
reaction mixture for 3 hours. The mixture is then heat-
ed at 60-65C for 2 hours, dissolved in benzene, washed
with water, dried and filtered. The filtrate is heated
at '50C/60 mm to remove volatile components. The resi-
due is the desired dimethyl ester.
The carboxylic ester derivatives which are des-
cribed above resulting from the reaction of an acylating
agent with a hydroxy containing compound such as an alco-
hol or a phenol may be further reacted with (F-3) an
amine, and particularly polyamines in the manner describ-
ed previously for the reaction of the acylating agent
(B-1) with amines (B-2) in preparing component (B). In
one embodiment, the amount of amine which is reacted
with the ester is an amount such that there is at least
about O.Ol equivalent of the amine for each equivalent
of acylating agent initially employed in the reaction
with the alcohol. Where the acylating agent has been
reacted with the alcohol in an amount such that there is
at least one equivalent of alcohol for each equivalent
of acylating agent, this small amount of amine is suffi-
2~3~'78~ ~
-81-
cient to react with minor amounts of non-esterified car-
boxyl groups which may be present. In one preferred
embodiment, the amine-modified carboxylic acid esters
utilized as component (F) are prepared by reacting about
l.0 to 2.0 equivalents, pre~erably about 1.0 to 1.8
equivalents of hydroxy compounds, and up to about 0.3
e~uivalent, preferably about 0.02 to about 0.25 equiva-
lent of polyamine per equivalent of acylating agent.
In another embodiment, the carboxylic acid
acylating agent may be reacted simultaneously with both
the alcohol and the amine~ There is yenerally at least
about 0.01 equivalent of the alcohol and at least 0.01
equivalent of the amine although the total amount of
equivalents o~ the combination should be at least about
0.5 equivalent per equivalent of acylating agent. These
carboxylic ester derivative compositions which are use-
ful as component (F) are known in the art, and the prep-
aration of a number of these derivatives is described
in, for example, U.S. Patents 3,957,854 and 4,234,435
which have been incorporated by reference previously.
The following specific examples illustrate the prepar-
ation of the esters wherein both alcohols and amines are
reacted with the acylating agent.
Example F-3
A mixture of 334 parts (0.52 equivalent) of the
polyisobutene-substituted succinic acylating agent pre-
pared in Example F-2, 548 parts of mineral oil, 30 parts
(0.88 equivalent) of pentaerythritol and 8.6 parts
(0.0057 equivalent) of Polyglycol 112-2 demulsifier from
Dow Chemical Company is heated at 150C for 2.5 hours.
The reaction mixture is heated to 210C in 5 hours and
held at 210C for 3.2 hours. The reaction mixture is
cooled to 190C and 8.5 parts (0.2 equivalent) of a com-
2'~7~
-82-
mercial mixture of ethylene polyamines having an average
of about 3 to about 10 nitrogen atoms per molecule are
added. The reaction mixture is stripped by heating at
205C with nitrogen blowing for 3 hours, then filtered
to yield the filtrate as an oil solution of the desired
product.
E~ample F-4
A mixture of 322 parts (0.5 equivalent) of the
polyisobutene-substituted succinic acylating agent pre-
pared in Example F-2, 68 parts (2.0 equivalents) of pen-
taerythritol and 508 parts of mineral oil is heated at
204-227C for 5 hours. The reaction mixture is cooled
to 162C and 5.3 parts ~0.13 equivalent) of a commercial
ethylene polyamine mixture having an average of about 3
to 10 nitrogen atoms per molecule is added. The reac-
tion mixture is heated at 1~2-163C for one hour, then
cooled to 130C and filtered. The filtrate is an oil
solution of the desired product.
Example F-5
A mixture o~ 1000 parts (0.495 mole) of polyiso-
butene having a number average molecular weight of 2020
and a weight average molecular weight of 6049 and 115
parts (1.17 moles) of maleic anhydride is heated to
184C over 6 hours, during which time 85 parts (1.2
moles) of chlorine are added beneath the surface. An
additional 59 parts (0.83 mole) of chlorine are added
over 4 hours at 184-189C. The mixture is blown with
nitrogen at 186-190C for ~6 hours. The residue is a
polyisobutene-substituted succinic anhydride having a
total acid number of 95.3.
A solution of 409 parts (0.66 equivalent) of
the substituted succinic anhydride in 191 parts of min-
eral oil is heated to 150C and 42.5 parts (1.19 equiv-
~2~33 78~
-83-
alent) o~ pentaerythritol are added over 10 minutes,
with stirring, at 145-150C. The mixture is blown with
nitrogen and heated to 205-210C over about 14 hours to
yield an oil solution of the desired polyester intermed-
iate.
Diethylene triamine, 4.74 parts (0.138 equiva-
lent), is added over one-half hour at 160C with stir-
ring, to 988 parts of the polyester intermediate (con-
taining 0.69 equivalent of substituted succinic acylat-
ing agent and 1.24 equivalents of pentaerythritol).
Stirring is continued at 160C for one hour, after which
289 parts of mineral oil are added. The mixture is
heated for 16 hours at 135C and filtered at the same
- temperature, using a ~ilter aid material. The filtrate
is a 35~ solution in mineral oil of the desired amine-
modified polyester. It has a nitrogen content of 0.16
and a residual acid number of 2Ø
Example F-6
- (a) A mixture of 1000 parts of polyisobutene
having a number average molecular weight of about 1000
and 108 parts (1.1 moles) of maleic anhydride is heated
to about 190C and 100 parts (1.43 moles) of chlorine
are added bene~th the surface over a period of about 4
hours while maintaining the temperature at about 185-
190C. The mixture then is blown with nitrogen at this
temperature for several hours, and the residue is the
desired polyisobutene-substituted succinic acylating
agent.
(b) A solution of 1000 parts of the acylating
agent preparation (a) in 857 parts of mineral oil is
heated to about 150C with stirring, and 109 parts (3.2
equivalents) of pentae~ythritol are added with stirring.
The mixture is blown with nitrogen and heated to about
.
-84-
200C over a period of about 14 hours to form an oil
solution of the desired carboxylic ester intermediate.
To the intermediate, there are added 19.25 parts (.46
equivalent) of a commercial mixture of ethylene poly-
amines having an average of about 3 to about 10 nitrogen
atoms per molecule. The reaction mixture is stripped by
heating at 205C with nitrogen blowing for 3 hours and
filtered. The filtrate is an oil solution (45~ oil) of
the desired amine-modified carboxylic ester which con-
tains 0.35% nitrogen.
Example F-7
(a) A mixture of 1000 parts [0.495 mole) of
polyisobutene having a number average molecular weight
of 2020 and a weight average molecular weight of 6049
and 115 parts (1.17 moles) of maleic anhydride is heated
to 184C over 6 hours, during which time 85 parts (1.2
moles~ of chlorine are added beneath the surface. An
additional 59 parts (0.83 mole) of chlorine are added
over 4 hours at 184-189C. The mixture is blown with
nitrogen at 186-190C for 26 hours. The residue is a
polyisobutene-substituted succinic anhydride having a
total acid number of 95.3.
~ (b) A solution of 409 parts (0.66 equivalent)
of the substituted succinic anhydride in 191 parts of
mineral oil is heated to 150C and 42.5 parts (1.19
equivalent) of pentaerythritol are added over 10 min-
utes, with stirring, at 145-150C. The mixture is blown
with nitrogen and heated to 205-210C over about 14
hours to yield an oil solution of the desired polyester
intermediate.
Diethylene triamine, 4.74 parts (0.138 equiva-
lent), is added over one-half hour at 160C with stir-
ring, to 988 parts of the polyester intermediate (con-
78~9
taining 0.69 equivalent of substituted succinic acylat-
ing agent and 1.24 equivalents of pentaerythritol).
Stirring is continued at 160C for one hour, after which
289 parts of mineral oil are added. The mixture is
heated for 16 hours at 135C and filtered at the same
tempera~ure, using a filter aid material. The filtrate
is a 35~ solution in mineral oil of the desired amine-
modified polyester. It has a nitrogen content of 0.16%
and a residual acid number of 2Ø
The lubricating oil compositions of the present
invention also may contain, and preferably do contain,
other additives to import certain desirable properties
to the lubricant. For example, the oils may contain at
least one friction modifier to provide the lubricating
oil with the proper frictional characteristicsr Various
amines, particularly tertiary amines are effective fric-
tion modifiers. Examples of tertiary amine friction
modifiers include N-fatty alkyl-N,N-diethanol amines,
N-fatty alkyl-N,N-diethoxy ethanol amines, etc. Such
tertiary amines can be prepared by reacting a fatty
alkyl amine with an appropriate number of moles of ethyl-
ene oxide. Tertiary amines derived from naturally occur-
~ing substances such as coconut oil and oleoamine are
available from Armour Chemical Company under the trade
designation "Ethomeen". Particular examples are the
Ethomeen-C and the Ethomeen-O series.
Sulfur-containing compounds such as sulfurized
C12-24 fats, alkyl sulfides and polysulfides wherein
the alkyl groups contain from 1 to 8 carbon atoms, and
sulfurized polyolefins also may function as friction
modifiers in the lubricating oil compositions of the
invention.
-86-
In one embodiment, a preferred friction modifi-
er to be included in the lubricating oil compositions of
the present invention is at least one partial fatty acid
ester of a polyhydric alcohol, and generally, up to
about 1% by wei~ht of the partial fatty acid esters
appears to provide the desired friction-modifying char-
acteristics. The hydroxy fatty acid esters are select-
ed from hydroxy fatty acid esters of dihydric or polyhy-
dric alcohols or oil-soluble oxyalkylenated derivatives
thereof.
Suitable partial fatty acid esters of polyhy-
dric alcohols include, for example, glycol monoesters,
glycerol mono- and diesters,- and pentaerythritol di-
and/or triesters. The partial fatty acid esters of gly-
cerol are preferred, and of the glycerol esters, mono-
esters, or mixtures of monoesters and diesters are often
utilized. The partial fatty acid esters of polyhydric
alcohols can be prepared by methods well known in the
art, such as by direct esterification of an acid with a
polyol, reaction of a fatty acid with an epoxide, etc.
It is generally preferred that the partial fat-
ty acid ester contain olefinic unsaturation, and this
~lefinic unsaturation usually is found in the acid moi-
ety of the ester. In addition to natural fatty acids
containing olefinic unsaturation such as oleic acid,
octeneoic acids, tetradeceneoic acids, etc., can be
utilized in forming the esters.
The partial fatty acid esters utilized as fric-
tion modifiers in the lubricating oil compositions of
the present invention may be present as components of a
mixture containing a variety of other components such as
unreacted fatty acid, fully esterified polyhydric alco-
hols, and other materials. Commercially available
Z~ 7~
-87-
partial fatty acid esters often are mixtures which con-
tain one or more of these components as well as mixtures
of mono- and diesters of glycerol.
Among the commercially available glycerol
esters are ester mixtures containing at least about 30%
by weight of monoester and generally from about 35% to
about 65% by weight of monoester, about 30% to about 50%
by weight of diester, and the balance in the aggregate,
generally less than about 15%, is a mixture of triester,
free fatty acid and other components. Specific examples
of commercially available material comprising fatty acid
esters of glycerol include ~mery 2421 (Emery Industries,
Inc.), Cap City GMO (Capital), DUR-EM 114, DUR-EM GMO,
etc. ~Durkee Industrial Foods, Inc.) and various mater-
ials identified under the mark MAZOL GMO (Mazer Chemi-
cals, Inc.~. Other examples of partial fatty acid
esters of polyhydric alcohols may be found in K.S.
Markley, Ed., "Fatty Acids", Second Edition, Parts I and
V, Interscience Publishers (1968). Numerous commercial-
ly available fatty acid esters of polyhydric alcohols
are listed by tradename and manufacturer in McCutcheons'
Emulsifiers and Detergents, North American and Interna-
tional Combined Editions (1981).
The lubricating oil compositions of the present
inve~tion also may contain at least one neutral or basic
alkaline earth metal salt of at least one acidic organic
compound. Such salt compounds ~enerally are referred to
as ash-containing detergents. The acidic organic com-
pound may be at least one sulfur acid, carboxylic acid,
phosphorus acid, or phenol, or mixtures thereof. Gener-
ally, the basic or overbased salts are preferred. The
basic or overbased salts will have metal ratios of up to
about 40 and more particularly from about 2 to about 30
or 40
zn~78~3
-88-
Calcium, magnesium, barium and strontium are
the preferred alkaline earth metals. Salts containing a
mixture of ions of two or more of these alkaline earth
metals can be used.
A commonly employed method for preparing the
basic (or overbased) salts comprises heating a mineral
oil solution of the acid with a stoichiometric excess of
a metal neutralizing agent, e.g., a metal oxide, hydrox-
ide, carbonate, bicarbonate, sulfide, etc., at tempera-
tures above about 50C. ~n addition, various promoters
may be used in the neutralizing process to aid in the
incoxporation of the large excess of metal. These pro-
moters include such compounds as the phenolic sub
stances, e.g., phenol, naphthol, alkylphenol, thiophen-
ol, sulfurized alkylphenol and the various condensation
products of formaldehyde with a phenolic substance; alco-
hols such as methanol, 2-propanol, octyl alcohol, cello-
solve carbitol, ethylene, glycol, stearyl alcohol, and
cyclohexyl alcohol; amines such as aniline, phenylenedi-
amine, phenothiazine, phenyl-beta-naphthylamine, and
dodecyl amine, etc. A particularly effective process
for preparing the basic salts comprises mixing the acid
with an excess of the basic alkaline earth metal in the
presence of the phenolic promoter and a small amount of
water and carbonating the mixture at an elevated tempera-
ture, e.g., 60~C to about 200C.
As mentioned above, the acidic organic compound
from which the salt alkaline earth metal is derived may
be at least one sulfur acid, carboxylic acid, phosphorus
acid, or phenol or mixtures thereof. Some of these
acidic organic compounds (sulfonic and carbo~ylic acids)
previously have been described above with respect to the
preparation of the alkali metal salts (component (E)),
zn~L7~
-89-
and all of the acidic organic compounds described above
can be utilized in the preparation of the alkaline earth
metal salts. In addition to the sulfonic acids, the
sulfur acids include thiosulfonic, sulfinic, sulfenic,
partial ester sulfuric, sulfurous and thiosulfuric
acids.
The pentavalent phosphorus acids may be an
organophosphoric, phosphonic or phosphinic acid, or a
thio analog of any of these.
The alkaline earth metal salts may also be
prepared from phenols; that is, compounds containing a
hydroxy group bound directly to an aromatic ring. The
term "phenol" as used herein includes compounds having
more than one hydroxy group bound to an aromatic ring,
such as catecholl resorcinol and hydroquinone. It also
includes alkylphenols such as the cresols and ethyl-
phenols, and alkenylphenols. Preferred are phenols
containing at least one alkyl substituent containing
about 3-100 and especially about 6-50 carbon atoms, such
as heptylphenol, octylphenol, dodecylphenol, tetrapro-
pene-alkylated phenol, octadecylphenol and polybutenyl-
phenols. Phenols containing more than one alkyl substi-
tuent may also be used, but the monoalkylphenols are
preferred because of their availability and ease of
production.
Also useful are condensation products of the
above~described phenols with at least one lower aldehyde
or ketone, the term "lower" denoting aldehydes and
ketones containing not more than 7 carbon atoms. Suit-
able aldehydes include formaldehyde, acetaldehyde, pro-
pionaldehyde, etc.
The amount of alkaline earth metal salt includ-
ed in the lubricants of the present invention also may
Zf3~l7~3~9
--90--
be varied over a wide range, and useful amounts in any
particular lubricating oil composition can be readily
determined by one skilled in the art. The salts func-
tion as auxiliary or supplemental detergent. The amount
contained in a lubricant of the invention may vary from
about 0% to about 5% or more.
The lubricating oils of the invention may con-
tain at least one neutral or basic alkaline earth metal
salt of an alkylphenol sulfide. The oils may contain
from about 0 to about 2 or 3% of said phenol sulfides.
~ore often, the oil may contain from about 0.01 to about
2% by weight of the basic salts of phenol sulfides. The
term "basic" is used herein the same way in which it was
used in the definition of other components above. The
neutral and basic salts of phenol sulfides provide anti-
oxidant and detergent properties of the oil compositions
of the invention.
The oil compositions of the present invention
also may contain one or more sulfur-containing composi-
tion useful in improving the antiwear, extreme pressure
and antioxidant properties of the lubricating oil compo-
sitions. Sulfur-containing compositions prepared by the
sulfurization of various organic materials including
olefins are useful. The olefins may be an~ aliphatic,
arylaliphatic or alicyclic olefinic hydrocarbon contain-
ing from about 3 to about 30 carbon atoms.
U.S. Patents 4,119,549, 4,505,830 and Re 27,331
are incorporated by re~erence herein for their disclo-
sure of suitable sulfurized olefins useful in the lubri-
cating oils of the present invention. Several specific
sulfurized compositions are described in the wor~ing
examples thereof~
Z~33L7~1~
-91-
Other extreme pressure agents and corrosion-
and oxidation-inhibiting agents also may be included and
are exemplified by chlorinated aliphatic hydrocarbons
such as chlorinated wax; organic sulfides and polysul-
fides such as benzyl disulfide, bis(chlorobenzyl)disul-
fide, dibutyl tetrasulfide, sulfurized methyl ester of
oleic acid and sulfurized alkylphenol; phosphosulfurized
hydrocarbons such as the reaction product of a phos-
phorus sulfide with turpentine or methyl oleate; phos-
phorus esters including principally dihydrocarbon and
trihydrocarbon phosphites such as dibutyl phosphite,
diheptyl phosphite, dicyclohexyl phosphite, pentyl
phenyl phosphite, dipentyl phenyl phosphite, tridecyl
phosphite, distearyl phosphite, dimethyl naphthyl
phosphite, oleyl 4-pentylphenyl phosphite, polypropylene
(molecular weight 500)-substituted phenyl phosphite,
diisobutyl-substituted phenyl phosphite; metal thiocar-
bamates, such as zinc dioctyldithiocarbamate, and barium
heptylphenyl dithiocarbamate.
Pour point depressants are a particularly use-
ful type of additive often included in the lubricatiny
oils described herein. The use of such pour point
depressants in oil-based compositions to improve low
temperature properties of oil-based compositions is well
known in the art. See, for example, page 8 of "Lubric-
ant Additives" by C.V. Smalheer and R. Kennedy Smith
Lezius-Hiles Co. publishers, Cleveland, Ohio, 1967.
Examples of useful pour point depressants are
polymekhacrylates; polyacrylates; polyacrylamides; con-
densation products of haloparaffin waxes and aromatic
compounds; vinyl carboxylate polymers; and terpolymers
of dialkylfumarates, vinyl esters of fatty acids and
alkyl vinyl ethers. Pour point depressants useful for
2')~7~9
-92-
the purposes of this invention, techniques for their
preparation and their uses are described in U.S. Patents
2,387,501; 2,015,748; 2,655,479; 1,815,022; 2,191,498;
2,666,746; 2,721,877; 2,721,878; and 3,250,715 which are
hereby incorporated by reference for their relevant
disclosures.
Anti-foam agents are used to reduce or prevent
the formation of stable foam. Typical anti-foam agents
include silicones or organic polymers. Additional anti-
oanl compositions are described in "Foam Control Agents"
by Henry T. Kerner (Noyes Data Corporation, 1976), pages
125-162.
The lubricating oil compositions of the present
invention also may contain, particularly when the lubri-
cating oil compositions are formulated into multigrade
oils, one or more commercially available viscosity modi-
fiers. Viscosity modifiers generally are polymeric mat-
erials characterized as being hydrocarbon-based polymers
generally having number average molecular weights be-
tween about 25,000 and 500,000 more often between abou~
50,000 and 200,000.
Polyisobutylene has been used as a viscosity
modifier in lubricating oils. Polymethacrylates (PMA)
are prepared from mixtures of methacrylate monomers
having different alkyl groups. Most PMA's are viscosity-
modifiers as well as pour point depressants. The alkyl
groups may be either straight chain or branched chain
groups containing ~rom 1 to about 18 carbon atoms.
When a small amount of a nitrogen-containing
monomer is copolymerized with alkyl methacrylates,
dispersancy properties also are incorporated into the
product. Thus, such a product has the multiple function
of viscosity modification, pour point depressants and
Z(~7~3~9
-93-
dispersancy. Such products have been referred to in the
art as dispersant-type viscosity modifiers or simply
dispersant-viscosity modifiers. Vinyl pyridine, N-vinyl
pyrrolidone and N,N'-dimethylaminoethyl methacrylate are
examples of nitrogen-containing monomers. Polyacrylates
obtained from the polymerization or copolymerization of
one or more alkyl acrylates also are useful as viscosi-
ty-modifiers.
Ethylene-propylene copolymers, generally refer-
red to as OCP can be prepared by copolymerizing ethylene
and propylene, generally in a solvent, using known catal-
ysts such as a Ziegler-Natta initiator. The ratio of
ethylene to propylene in the polymer influences the oil-
solubility, oil-thickenin~ ability, low temperature vis-
cosity, pour point depressant capability and engine per-
formance of the produGt. The common range of ethylene
content is 45-60% by weight and typically is from 50% to
about 55~ by weight. Some commercial OCP's are terpoly-
mers of ethylene, propylene and a small amount of non-
conjugated diene such as 1,4-hexadiene. In the rubber
industry, such terpolymers are referred to as EPDM
(ethylene propylene diene monomer). The use of OCP's as
viscosity modifiers in lubricating oils has increased
rapidly since about 1970, and the OCP's are currently
one of the most widely used viscosity modifiers for
motor oil~.
Esters obtained by copolymerizing styrene and
maleic anhydride in the presence of a free radical ini-
tiator and thereafter esterifying the copolymer with a
mixture of C4_18 alcohols also are useful as viscosity
modifying additives in motor oils. The styrene esters
generally are considered to be multifunctional premium
viscosity modifiers. The styrene esters in addition to
~S~178~
-94-
their viscosity modifying properties also are pour point
depressants and exhibit dispersancy properties when the
esterification is terminated before its completion leav-
ing some unreacted anhydride or carboxylic acid groups.
These acid groups can then be converted to imides by
reaction with a primary amine. Hydrogenated styrene-con-
jugated diene copolymers are another class of commercial-
ly available viscosity modifiers for motor oils.
The above described ~hydrogenated copolymers
have been described in the prior art such as in U.S.
Patents 3,551,336; 3,598,738; 3,554,911; 3,607,749;
3~687,849; and ~,181,618 which are hereby incorporated
by reference for their disclosures of polymers and
copolymers useful as viscosity modifiers in the oil
compositions of this invention. Hydrogenated styrene-
butadiene copolymers useful as viscosity modifiers in
the lubricating oil compositions of the present inven-
tion are available commercially from, for example, BASF
under the general trade designation "Glissoviscal". A
particular e~ample is a hydrogenated styrene-butadiene
copolymer available under the designation Glissoviscal
5260 which has a molecular weight, determined by gel
permeation chromatography, of about 120,000. Hydro-
genated styrene-isoprene copolymers useful as viscosity
modifiers are available from, for example, The Shell
Chemical Company under the general trade designation
"Shellvis". Shellvis 40 from Shell Chemical Company is
identified as a diblock copolymer of styrene and iso-
prene having a number average molecular weight of about
155,000, a styrene content of about 19 mole percent and
an isoprene content of about 81 mole percent. Shellvis
50 is available from Shell Chemical Company and is ident-
ified as a diblock copolymer of styrene and isoprene
Z(~7~
-95-
having a number average molecular weight of about
100,000, a styrene content of about 28 mole percent and
an isoprene content of about 72 mole percent. General-
ly, the polymeric viscosity improvers are used in concen-
trations of about 0.2 to about 8% and more particularly,
in amounts from about 0.5 to about 6~ by weight of the
finished lubricating oil.
The lubricating oils of the present invention
may be prepared by dissolving or suspending the various
components directly in a base oil along with any other
additives which may be used. More often, the chemical
components of the present invention are diluted with a
substantially inert, normally liquid oryanic diluent
such as mineral oil, naphtha, benzene, etc. to form an
additive concentrate. These concentrates usually
comprise from about 0.01 to about 80% by weight of one
or more -of the additive components (A) through (C)
described above, and may contain, in addition, one or
more of the other additives described above. Chemical
concentrations such as 15%, 20%, 30% or 50% or higher
may be employed.
For example, concentrates may contain on a
~hemical basis, from about 10 to about 50% by weight of
the carboxylic derivative composition (B), and ~rom
about 10 to about 5000 ppm of manganese as metal. The
concentrates also may contain from about 0.01% to about
15% of the metal phosphorodithioates (D), ~rom about 1
to about 30% by weight of the rarboxylic ester (F)
and/or from about 1% to about 20~ by weight of at least
one neutral or basic alkali metal salt (F).
Typical lubricating oil compositions according
to the present invention are exemplified in the follow-
ing lubrication oil examples wherein the percentages are
781~
-96-
on a volume basis and the percentages indicate the
amount of the normally oil diluted solutions of the
indicated additives used to form the lubricating oil
composition. For example, Lubricant I contains 3.5% by
volume of the product of Example B-10 which is an oil
solution of the indicated carboxylic derivative tB)
containing 55~ diluent oil.
Lubricant Example I
Components Percent
Product of Ex. B-10 3.5
Product of Ex. D-1 0.4
Zinc salt of a phosphorodithioic
acid prepared from amyl and
isobutyl alcohol mixture ~35:65)m 0.47
Product of Ex. E-1 0.25
Basic magnesium alkylated benzene
benzene sulfonate 0.33
Basic calcium alkylated benzene
sulfonate 0.41
Overbased manganese carboxylate
(40% Mn) (Mooney FOA-910) 250 ppm
Amide-based friction modifier 0.1
Cg mono- and Cg-di-para-alkylated
diphenylamine 0.1
Sulfurized butyl acrylate-butadiene
product 0.15
Silicone antifoam 0.006
Mineral oil remainder
2~ 7~
-97-
Lubricant Example II
ComPOnent Percent
Product of Ex. B-10 3.0
zinc salt of diisooctyl phos-
phorodithioic acid 1-07
Product of Ex. F-6 2.8
Basic magnesium sulfonate 0.35
Basic calcium sulfonate 0.92
Nonyl phenoxy poly(ethyleneoxy)
ethanol 0.1
Overbased manganese carboxylate
t40% Mn) - Mooney FOA-910 250 ppm
Propylene tetramer phenol reacted
with sulfur dichloride 2.3
Silicone antifoam 0.001
Mineral oil remainder
-
The lubricating oil compositions of the present
invention exhibit a reduced tendency to deteriorate
under conditions of use and thereby reduce wear and the
formation of such undesirable deposits as varnish,
sludge, carbonaceous materials and resinous materials
which tend to adhere to the various engine parts and
reduce the efficiency of the engines. In one embodi-
ment, lubricating oils can be formulated within this
invention which can pass all of the tests required for
classification as an SG oil.
The lubrication oils of this invention are use-
ful also in diesel engines, and lubricating oil formula-
tions can be prepared in accordance with this invention
which meet the requirements of the new diesel classifica-
tion CE.
Z~3~7~
-98-
The performance characteristics of the lubricat-
ing oil compositions of the present invention are evalu-
ated by subjecting lubricating oil compositions to a
number of engine oil tests which have been designed to
evaluate various per~ormance characteristics of engine
oi~s
The ~STM Sequence IIID engine oil test simul-
ates high speed, high load operation and is a severe
test of an oil's ability to lubricate under demanding
conditions. This test utilizes a production 5.7 liter,
2-barrel 8.5:1 compression Oldsmobile V-8 gasoline
engine. Each test requires that the engine be built to
the specific instructions outlined in ASTM STP 315H.
The test is conducted in two parts consisting of a
4-hour break-in period followed by a 64-hour steady-
state test period. The engine is operated at 100 bhp/-
74.6 kw and 3000 rpm during the 64-hour test period. The
test is monitored by sampling and analyzing the lubric-
ant every 8 hours. New test oil is added to replenish
the oil lost to sampling and blowby.
The performance criteria for the Sequence IIID
test (SF Quality) are as follows: maximum viscosity
increase measured at 45C after 64 hours = 375%; average
engine sludge rating 9.2 minimum; average engine piston
rating 9.2 minimum; average oil land deposits 4.8
minimum; cam and lifter wear (inches), average = 0.0040,
and maximum = 0.0080; and oil consumption, quarts =
6.38.
The results of the Sequence IIID test modified
to use non-phosphated cam shafts and conducted on
Lubricants I and II and Control Lubricants I and II are
summarized in the following table. Control Lubricants I
and II are identical to Lubricants I and II respectively
7~
_99_
except that the Controls contain no manganese. (The
normal Sequence IIID cam shafts are manganese phosphated
to enhance scuffing resistance and to provide a lubric-
ant reservoir in the contact zone.) Results of the
tests are reported in the following table.
~'3178~9
-loo-
N O O
~D ~ ~OO O U~
~ O
_C 0
~ E o o o
O Ir~ O O O
o- ~ I~ oo o
0 4 41~ /~ ~o O O /`
4 _C 4 O ~ ~ ~O O o O
. -u~
C ~ 4~ 0 0
O ~ _ a~ o o o
O O a a-~D O O O N ~t
~n
V~
e c u~
~q #
c
L ~ c
O
S_ OllS 4
a
~, -o 3 ~ c c
Cl ~ JC~ L
4 v ~ ,_,
Y FE C~:~
C 1~ V ~ . ~
4 o V o o.~:~E E L u~ O o
n L ~ L~"~C > o
~ J ~ C~E EE
~ ~ O ~
Z!~78~9
-101-
As mentioned above, in order for a lubricating
oil to be qualified ~or API Service Classification SG,
the lubricating oils must pass certain specified engine
oil tests. ~owever, lubricating oil compositions
passing one or more of the individual tests also are
useful in certain applications.
The ASTM Sequence IIIE engine oil test has been
recently established as a means of defining the
high-temperature wear, oil thickening, and deposit pro-
tection capabilities of SG engine oils. The IIIE test,
which replaces the Sequence IIID test, provides improved
discrimination with respect to high temperature camshaft
and lifter wear protection and oil thickening control.
The IIIE test utilizes a Buick 3.8L V-6 model engine
which is operated on leaded fuel at 67.8 bhp and 3000
rpm for a maximum test length of 64 hours. A valve
spring load of 230 pounds is used. A 100% glycol cool-
ant is used because of the high engine operating tempera-
tures. Coolant outlet temperature is maintained at
118C, and the oil temperature is maintained at 149C at
an oil pressure of 30 psi. The air-to-fuel ratio is
16.5, and the blow-by rate is 1.6 cfm. The initial oil
charge is l46 ounces.
The test is terminated when the oil level
reaches 28 ounces low at any of the 8-hour check inter-
vals. When the tests are concluded before 64 hours be-
cause of low oil level, the low oil level has generally
resulted from hang-up of the heavily oxidized oil
throughout the engine and its inability to drain to the
oil pan at the 49C oil check temperature. Viscosities
are obtained on the 8-hour oil samples, and from this
data, curves are plotted of percent viscosity increase
versus engine hours. A maximum 375% viscosity increase
Z~ L781 ~9
-102-
measured at 40C at 64 hours is required for API class-
ification SG. The engine sludge requirement is a mini-
mum rating of 9.2, the piston varnish a minimum of 8.9,
and the ring land deposit a minimum of 3.5 based on the
CRC merit rating system. Details of the current
Sequence IIIE Test are contained in the "Sequence IIID
Surveillance Panel Report on Sequence III Test to the
ASTM Oil Classification Panel", dated November 30, 1987,
revised January 11, 1988.
The results of the Sequence IIIE test conducted
on Lubricants I and II are summarized in the following
Table III. For comparison, results are also summarized
for Control Oil I and Control Oil 2 which corresponded
to Lubricants I and II, respectively except that the
control oils do not contain the manganese additive.
TABLE III
ASTM Sequence III-E Test
__ Test Results _ _ _
O i 1
% Vis Engine Piston Rlng Land VTWa Consumption
Lub. Increase Sludae Varnish DePoslt Max/Mln/Avq (qts)
Cont I 3300 9.3 3.4 5.0 106/7~19 2.7
I 210 9.6 8.9 6.3 12/7/9 1.9
Cont II 2400 9.2 8.8 3.7 1175/3/176 3.1
II 740 9.3 9.0 4.5 133/6~70 3.6
a In ten-thousandths of an inch.
While the invention has been explained in rela-
tion to its preferred embodiments, it is to be under-
stood that various modifications thereof will become
apparent to those skilled in the art upon reading the
specification. Therefore, it is to be understood that
zn3~8~9
-103- .
the invention disclosed herein is intended to cover such
modifications as fall within the scope of the appended
claims.
