Note: Descriptions are shown in the official language in which they were submitted.
-1- 1 3 3 6 9 0 2
BACKGROUND OF THE INVE~llrION
FIEID OF T~ Ihv~NllON
This invention relates to oil soluble additive
mixtures useful in fuel and lubricating oil compositions,
including concentrates containing said additives, and
methods for their manufacture and use. The additive
mixture comprises an ashless non-borated dispersant, copper
antioxidant, and friction modifiers having improved storage
stability.
DESCRIPTION OF THE PRIOR AR'r
Heretofore, many lubricants and fuels have
contained compounds known as friction modifiers (also
termed "lubricity additives"), which act to reduce the
friction of internal engine parts and thereby increase fuel
economy. U.S. Patent 3,429,817 relates to the improvement
of the lubricity and load carrying ability of a synthetic
ester lubricating oil by addition of an ester formed by
reacting about 2 moles of C2 to C5 glycol with about 1
mole of C36 dicarboxylic acid dimer of a C18
unsaturated fatty acid (e.g., linoleic acid or oleic
acid). U.S. Patent 3,273,g81 is directed to fuels and
lubricating oil containing as lubricating additive a
mixture of dimer acids and polyhydric alcohol partial
esters. U.S. Patent 4,459,223 relates to lubricating oil
friction reducing additives which are the reaction product
of a dimer carboxylic acid (e.g., linoleic acid dimers) and
a pol~hydric alcohol having at least 3 hydroxyl groups.
U. S . Patent 4, 479, 883 relates to lubricating oil
compositions having a relatively low level of phosphorous
and improved friction reducing properties by use of a
'$~
1 336902
-2-
mixturo Or a glycol or glycerol ester o~ a polycarboxylic
acid (e.g., linoleic acid dimers) with Mo, Zn, or Sb
dithiocarbamates. U.S. Patent 4,557,846 relates to
lubricating oil friction reducing additives comprising oil
soluble hydroxyamide compounds prepared by condensing a
dimer carboxylic acid (e.g., linoleic acid dimer~) with a
hydroxyamine. U.S. Patent 4,617,026 relates to fuel
friction modifying additive~ comprising hydroxyl-containing
esters of a C12 to C30 monocarboxylic acid and a glycol
or trihydric alcohol, wherein the glycol can comprise
polyalkylene glycol~ having 2 to 100 oxyalkylene repeat
units. U.S. Patent 4,683,069 relates to lubricating oil
fuel economy additives comprising glycerol partial esters
of C16-C18 fatty acids.
The instability, and hence the need for a
stabilization of, compositions containing polycarboxylic
acid-glycol ester~, ashles~ dispersant and certain metal
lubricating oil additives has been noted in the art. U.S.
Patent 4,105,571 is directed to storage stable lubricating
compositions having improved anti-friction and anti-wear
properties containing a zinc dihydrocarbyldithiophosphate,
an ester of a polycarboxylic acid and a glycol, and an
ashless high molecular weight dispersant, wherein either
the zinc or ester component, or both, are predispersed with
the ashless dispersant prior to adding them to the
lubricating composition. The friction modifying esters are
disclosed to include linoleic acid dimers which are
esterified with glycol such as diethylene glycol.
U.S. Patent 4,388,201 discloses lubricating oil
compositions containing such polycarboxylic acid-glycol
friction modifier esters in combination with borated or
non-borated alkenyl succinimide dispersants, by the
addition of small proportions of a co-dispersant comprising
an oil-soluble hydrocarbyl substituted mono- or
bis-oxazoline or lactone oxazoline.
3 1 3369G2
U.S. Patent 4,505,829 discloses lubricating oil
composition~ containing polycarboxylic acid, glycol esters
as friction modifiers in combination with hydrocarbon
soluble alkenyl succinimide dispersants with reduced
tendency towards formation of sediment upon storage. The
storage stability is improved by the addition thereto of
small proportions of polyol or polyol anhydride partial
esters of a fatty acid or an ethoxylated fatty acid, amine
or amide compound.
U.S. Patent 4,617,134 relates to storage stable
lubricating oil compositions comprising an additive
combination of a polycarboxylic acid glycol or glycerol
est e r, as frict ion m od ifier, and z inc
dihydrocarbyldithiophosphate and an ashless dispersant
containing a selected amount of free hydroxyl groups.
U.S. Patent 4,684,473 relates to solubilization of
oxygenated (hydroxy) esters of a dimer acid (including
linoleic dimer esters of polyhydric alcohols) by the
incorporation in the lubricating composition of an
C4-C23 oil soluble alkanol or an oil soluble alkyl
phosphate. It is disclosed that the selection of the chain
length of the alcohol is critical.
European Patent 24,146 relates to lubricating
compositions containing oil-soluble copper compounds in an
amount sufficient to retard or inhibit oxidation of the
lubricant during usQ (S to 500 ppm Cu) , and discloses that
such lubricant compositions can further comprise from 1 to
10 wt.% ashless dispersant compounds. Preferred are
dispersants derived from polyisobutenyl succinic anhydride
and polyethylene-amines, which dispersants can be further
modified with a boron compound to provide about 0.1 to 10
atomic proportions of boron per mole of the acylated
nitrogen compound. In addition, the patent discloses that
the lubricant compositions can also contain rust inhibitors
such as lecithin, sorbitan monooleate, dodecyl succinic
anhydride or ethoxylated alkyl phenols; and other additives
1 336902
--4--
such a~ pour point depressants, viscosity index improvers,
other antioxidants (e.g., zinc dialkyldithiophosphates),
basic alkaline earth metal detergents, etc. Illustrative
of oil-soluble copper compounds are copper dihydrocarbyl
thio- or dithio-phosphates, copper salts of a synthetic or
natural carboxylic acid (e.g., C10 to C18 fatty acids,
oleic acid, naphthenic acids) and the like.
U.S. Patent 4,552,677 relates to compositions
comprising copper salts of substituted succinic anhydride
derivatives containing a hydrocarbon-based substituent
group containing from about 8 up to about 35 carbon atoms,
which the patentee indicates are effective antioxidants for
crackcase lubricants.
U.S. Patent 3,509,052 relates to lubricating oil
compositions containing a lubricating oil, a dispersant
(which is a derivative of a substituted succinic acid where
the substituent contains at least 50 aliphatic carbon
atoms), and a demulsifier, e.g., polyoxyalkylene polyols,
together with other additives, such as rust inhibitors,
oxidation and corrosion inhibitors. The dispersant is said
to also permissibly comprise boron post-treated
alkyl-substituted succinimides, or metal salts of
substituted succinic acids (wherein the metal is preferably
a Group I or II metal, Al, Pb, Sn, Co, Ni or Zn).
European Patent 92,946 relates to the combination
of oil-soluble copper compounds with glycerol fatty acid
esters as fuel economy additives.
U.S. Patent 2,356,661 deals with lubricating oils
containing 50 to 100 parts per million of copper together
with an oil-soluble organic sulphur compound to provide
more stable lubricants which can be employed in internal
combustion engines over longer periods of time without
causing objectional increase in the viscosity of the oils
and with the formation of less deposits in the engine and
with less corrosion of sensitive bearing metals. U.S .
Patents 2,343,756 and 2,356,662 disclose the addition of
1 336902
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copper compounds, in conjunction with sulfur compounds, to
lubrlcating oils. In U.S. Patent 2,552,570, cuprous
thiophosphates are included in lubricant compositions at
relatively high levels, which results in undesirably~high
sulfated ash content. In U.S. Patent 3,346,493, a wide
variety of polymeric amine-metal reactants are employed as
detergents in lubricant compositions. In the two isolated
instances in which the metal is copper and the composition
contains zinc dihydrocarbyldithiophosphate, either the
amount of copper employed is outside the range of the
present invention or it is necessary that the oil insoluble
copper compound be complexed with the dispersant. U.S.
Patent 3,652,616 discloses a wide variety of polymeric
amine-metal reactants for addition to lubricating
compositions. U.S. Patent 4,122,033 discloses the entire
group of transition metal compounds as additives for
lubricants.
U.S. Patent 3,271,310 relates to metal salts of
alkenyl succinic acid, which are disclosed to be useful as
detergents and rust inhibitors in hydrocarbon oils and
which comprise metal salts of a hydrocarbon substituted
succinic acid having at least about 50 aliphatic carbon
atoms in the hydrocarbon substituent wherein the metal
comprises Group I, Group II, aluminum, lead, tin, cobalt or
nickel. The salts are disclosed to be useful in
lubricating oils in amounts of from 0.1 to about 20 wt.~
and in lubricating compositions for using gasoline internal
combu~tion engines in an amount of from 0.5 to about 5
wt.%. The salts are disclosed to be useful in combination
with ashless dispersants, including those which have been
borated by reaction with boric acid. Further, the salts
are indicated to be useful as emulsifying agents in water
in oil emulsions, and that when so employed, other emulsion
additives such as rust inhibitors can be used.
6- l 336902
.
U.S. Patent 3,351,647 relates to the phosphorus
and nitrogen containing reaction products formed by
reacting a metal salt of a phosphinodithioic acid with an
amine such as an aliphatic amine having from 1 to about 40
carbon atoms. Copper is among a group of metals disclosed
to be useful. The compositions are disclosed as additives
for lubricating oils and automatic transmission fluids, in
which they act as oxidation inhibitors and anti-wear
agents. These compositions are stated to be useful in
combination with ashless detergents such as the reaction
product of triethylenetetraamine with an alkenyl
sub~tituted succinic anhydride having at least 50 carbon
atoms in the alkenyl substituent.
U.S. Patent 3,401,185 relates to metal salts of
phosphorus acids, including copper salts of such acids,
useful in lubricating oils in combination with ashless
dispersants which may be borated.
U.S. Patent 3,328,298 relates to metal (e.g.,
copper) containing compositions formed by reacting a basic
inorganic metal compound with an intermediate formed by
reacting a phosphorothioic acid diester with an equimolar
amount of an epoxide. The resulting metal containing
compositions are disclosed to be useful in combination with
ashless dispersants.
U.S. Patent 4,417,990 relates to mixed metal
salts/sulfurized phenate compositions.
U.S. Patent 4,664,822 relates to certain copper
ore ba~ed metal containing compositions which are disclosed
to be useful in combination with other additives, among
which ashless containing dispersants (which can be
borated), zinc dialkyldithiophosphates, ash-containing
detergents, and ashless rust inhibitors are mentioned.
Canadian Patent 1,189,367 relates to hydrocarbon
soluble compositions containing a transition metal salt of
an organic acid, a hydrocarbon soluble ashless dispersant
and a phenolic antioxidant, which composition can
7 l 3 3 6 9 0 2
additionally comprise dye~, metal deactivators, and,
partlcularly, demulsifying agents. The transition metal
saltJ m~ntioned include copper organic salts, and the
organic acids include carboxylic acids, sulfonic acids and
phosphorus acids. It is indicated that the transition
metal salts used in the invention are often overbased and
contain an excess of one equivalent of metal per equivalent
of acid derived moiety.
U.S. Patent 4,5S2,677 relates to copper saltR of
hydrocarbyl substituted succinic acids wherein the
hydrocarbon group contains from about 8 to about 35 carbon
atoms. Such copper salts are said to be effective
antioxidants for crankcase lubricants without the
deleterious effect on rust and copper/lead bearing
corrosion performance that accompanies copper oleate, which
is described in European Patent 24,146, discussed abovo.
The copper salts of the '677 patent are said to be useful
in combination with other additives including ashless
dispersants which may be borated.
U.S. Patent 4,664,822 relates to lubricating oils
compositions comprising ashles~ dispersant and from 0.1 to
1.5 wt% of a copper overbased metal-containg composition as
dispersant/detergent, antioxidant and rust inhibitor
additive. It iR disclosed that the ashless dispersants may
be borated, and that the lubricating compositions can
contain additional conventional additives, among which are
mentioned friction modifiers. Disclosed as suitable
friction modifier~ are fatty acid derivatives comprising
esters such as triglycerides or monoesters from polyols
esters such as glycol monooleate and pentaerythritol
monooleate amides such as oleamide or amides made from
polyamineR or alkanolamines; and hereterocycles made by
condensing compunds such as aminoquanidine with carboxylic
acids to form triazoles. Further disclosed as suitable
friction modifiers are Mo compounds, and combinations of Na
sulfonates (or Mo compounds) and glycerol monoleates and
other fatty acid derivatives.
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SU~M~RY OF THE I~v~ ON
According to the present invention, friction
modified oleaginous compositions having improved storage
stability properties are provided, which comprise a
combination of (A) ashless dispersants, (B) friction
modifiers comprising glycol ester or hydroxyamine
derivatives of polycarboxylic acid~, and (C) oil-soluble
copper antioxidants, wherein the composition is
substantially free of boron and wherein preferably the
B:Cu weight ratio is less than about 0. 6: 1.
It has been surprisingly found that significantly
improved storage stability properties (that is, reduced
tendency to formation of sediment and haze) are achieved in
such compositions, and particularly in concentrates
indended for use in preparation of such compositions, by-
the requirement that such compositions be substantially
free of boron, thereby permitting the use of oil soluble
copper carboxylate antioxidants, such as copper oleate and
copper salts of polyalkylene substituted succinic
anhydrides.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to oleaginous
compositions comprising (A) ashless dispersants, (B)
friction modifiers comprising glycol ester and/or
hydroxyamide derivatives of certain polycarboxylic acids,
and (C) oil-soluble copper antioxidant compounds, wherein
the compo~ition is substantially free of boron.
The phrase "substantially free of boron" as used
in the instant specification and claims is intended to
refer to boron concentrations of less than 30 ppm by weight
boron. Preferably, the boron concentration of the
compositions of this invention are less than 20 ppm by
weight, more preferably less than 10 ppm by weight.
- -9- 1 3 3 6 9 0 2
ÇQE~onent A - A~hless DisDersants
Ashles~, nitrogen or ester containing dispersants
useful in this invention comprise boron-free members
selected from the group consisting of (i) oil soluble
salts, amides, imides, oxazoline~ and esters, or mixtures
thereof, of long chain hydrocarbon substituted mono and
dicarboxylic acids or their anhydrides; (ii) long chain
aliphatic hydrocarbon having a polyamine attached directly
thereto; and (iii) Mannich condensation products formed by
condensing about a molar proporticn of long chain
hydrocarbon substituted phenol with about 1 to 2.5 moles of
formaldehyde and about 0.5 to 2 mole~ of polyalkylene
polyamine; wherein said long chain hydrocarbon group in
(i), (ii) and (iii) is a polymer of a C2 to ClO, e.g.,
C2 to C5 monoolefin, said polymer having a number-_
average molecular weight of about 300 to about 5000.
A(i) The long chain hydrocarbyl substituted
dicarboxylic acid producing material, e.g. acid,
anhydride, or ester, used in the invention includes a long
chain hydrocarbon, generally a polyolefin, substituted
typically with an average of at least about 0.8, usefully
from about 1.0 to 2.0 (e.g. 1.0 to 1.6), preferably about
1.1 to 1.4 (e.g. 1.1 to 1.3) moles, per mole of
polyolefin, of an alpha- or beta-unsaturated C4 to C10
dicarboxylic acid, anhydride or ester thereof, such as
fumaric acid, itaconic acid, maleic acid , maleic
anhydride, chloromaleic acid, dimethyl fumarate,
chloromaleic anhydride, acrylic acid, methacrylic acid,
crotonlc acid, cinnamic acid, and mixtures thereof.
Preferred olefin polymers for reaction with the
unsaturated dicarboxylic acid anhydride or ester are
polymers comprising a major molar amount of C2 to ClO,
e.g. C2 to C5, monoolefin. Such olefins include
ethylene, propylene, butylene, isobutylene, pentene,
octene-l, styrene, etc. The polymers can be homopolymers
such as polyisobutylene, as well as copolymers of two or
lo- 1 3 3 6 9 0 2
more o~ such olefins such as copolymers of: ethylene and
propylene; butylene and isobutylene: propylene and
isobutylene; etc. Other copolymers include those in which
a minor molar amount of the copolymer monomers, e.g., 1 to
10 mole %, is a C4 to C18 non-conjugated diolefin,
e.g., a copolymer of isobutylene and butadiene; or a
copolymer of ethylene, propylene and 1,4-hexadiene; etc.
In some cases, the olefin polymer may be
completely saturated, for example an ethylene-propylene
copolymer made by a Ziegler-Natta synthesis using hydrogen
as a moderator to control molecular weight.
The olefin polymers will usually have number
average molecular weights within the range of about 700 and
about 5000, e.g. 700 to 3000, more usually between about
800 and about 2500, and will therefore usually have an
average of from about 50 to 400 carbon atoms. Particularly
useful olefin polymers have number average molecular
weights within the range of about 900 and about 2500 with
approximately one terminal double bond per polymer chain.
An especially useful starting material for a highly potent
dispersant additive made in accordance with this invention
is polyisobutylene.
Processes for reacting the olefin polymer with the
C4_10 unsaturated dicarboxylic acid, anhydride or ester
are known in the art. For example, the olefin polymer and
the dicarboxylic acid material may be simply heated
together as disclosed in U.S. patents 3,361,673 and
3,401,118 to cause a thermal "ene" reaction to take place.
Alternatively, the olefin polymer can be first halogenated,
for example, chlorinated or brominated to about 1 to 8 wt.
%, preferably 3 to 7 wt. % chlorine, or bromine, based on
the weight of polymer, by passing the chlorine or bromine
through the polyolefin at a temperature of 60 to 250C,
e.g. 120 to 160C. for about 0.5 to 10, preferably 1 to 7
hours. The halogenated polymer may then be reacted with
sufficient unsaturated acid or anhydride at 100 to 2S~-C,
usually about 180 to 220C. for about 0.5 to 10 hours,
1 336902
e.g. 3 to 8 hours, so the product obtained will contain an
averago of about l.o to 2.0 moles, preferably 1.1 to 1.4
mole~, e.g. 1.2 moles, of the unsaturated acid per mole of
the halogenated polymer. Processes of this general type are
taught in U.S. Patents 3,087,436; 3,172,892; 3,272,746 and
others.
Alternatively, the olefin polymer, and the
unsaturated acid material are mixed and heated while adding
chlorine to the hot material. Processes of this type are
disclosed in U.S. Patents 3,215,707; 3,231,587; 3,912,764;
4,110,349; 4,234,435; and in U.K. Pa~ent 1,440,219.
By the use of halogen, about 65 to 95 wt. % of the
polyolefin, e.g. polyisobutylene will normally react with
the dicarboxylic acid material. Upon carrying out a
thermal reaction without the use of halogen or a catalyst,
then usually only about 50 to 85 wt. % of the
polyisobutylene will react. Chlorination helps increase
the reactivity. For convenience, all of the aforesaid
functionality ratios of dicarboxylic acid producing units
to polyolefin, e.g. 1.0 to 2.0, etc. are based upon the
total amount of polyolefin, that is, the total of both the
reacted and unreacted polyolefin, present in the resulting
product formed in the aforesaid reactions.
Amine compounds useful as nucleophilic reactants
for neutralization of the hydrocarbyl substituted
dicarboxylic acid material include mono-and (preferably)
polyamines, mo~t preferably polyalkylene polyamines, of
about 2 to 60 (e.g. 2 to 6) , preferably 2 to 40, (e.g. 3
to 20) total carbon atoms and about 1 to 12 (e.g., 2 to 9),
preferably 3 to 12, and most preferably 3 to 9 nitrogen
atom~ in the molecule. These amines may be hydrocarbyl
amines or may be hydrocarbyl amines including other groups,
e.g, hydroxy groups, alkoxy groups, amide groups, nitriles,
imidazoline groups, and the like. Hydroxy amines with 1 to
6 hydroxy groups, preferably 1 to 3 hydroxy groups are
particularly useful. Preferred amines are aliphatic
saturated amines, including those of the general formulas:
3 3 6 ~ 0 2
-12-
R-~-R', and R-I-(CH2)9 - N (CH2)9 N
R" R' R''' R'
_ -t
(Ia) (Ib)
wherein R, R', R'' and R''' are independently selected from
the group consisting of hydrogen; C1 to C2S straight or
branched chain alkyl radicals; Cl to C12 alkoxy C2 to
C6 al~ylene radicals; C2 to C12 hydroxy amino
alkylene radicals; and C1 to C12 alkylamino C2 to
C6 alkylene radicals; and wherein R"' can additionally
comprise a moiety of the formula:
_ (CH2)s~ II (Ic)
_ ;t'
wherein R' is as defined above, and wherein each s and s'
can be the same or a different number of from 2 to 6,
preferably 2 to 4; and t and t' can be the same or
different and are each numbers of typically from O to 10,
preferably about 2 to 7, most preferably about 3 to 7, with
the proviso that t + t' is not greater than 10. To assure
a facile reaction it is preferred that R, R', R", R''',
(s), (s'), (t) and (t') be selected in a manner sufficient
to provide the compounds of formulas Ia and Ib with
typically at least one primary or secondary amine group,
preferably at least two primary or secondary amine groups.
This can be achieved by selecting at least one of said R,
R', R", or R''' groups to be hydrogen or by letting (t) in
formula Ib be at least one when R''' is H or when the (Ic)
moiety possesses a secondary amino group. The most
preferred amines of the above formulas are represented by
formula Ib and contain at least two primary amine groups
and at lea~t one, and preferably at least three, secondary
amine group9.
-13- 1 3 3 6 9 0 2
.
Non-limiting examples of suitable amine compounds
include: 1,2-diaminoethane; 1,3-diaminopropane;
1,4-diaminobutane; 1,6-diaminohexane; polyethylene amines
such as diethylene triamine; triethylene tetramine;
tetraethylene pentamine; polypropylene amines such as
1,2-propylene diamine; di-(1,2-propylene)triamine;
di- (1, 3 -p ropylene) triamine; N,N-dimethyl-
1,3-diaminopropane; N,N-di-(2-aminoethyl) ethylene diamine;
N,N-di(2-hydroxyethyl)-1,3-propylene diamine;
3-dodecylpropylamine; N-dodecyl-1,3-propane diamine; tris-
hydroxymethylaminomethane (THAM); diisopropanol amine;
diethanol amine; triethanol amine; mono-, di-, and
tri-tallow amines; amino morpholines such as
N-(3-aminopropyl) morpholine; and mixtures thereof.
Other useful amine compounds include: alicyclic
diamines such as 1,4-di(aminomethyl) cyclohexane, and
heterocyclic nitrogen compounds such as imidazolines, and
N-aminoalkyl piperazines of the general formula (II):
CH2 -CH2
H-NH-(CH2)p N ~' / N (CH2) - NH - H
_ nl CH2-CH2 -- n2-- P2 ~n3
wherein Pl and P2 are the same or different and are
each integers of from 1 to 4, and nl, n2 and n3 are
the same or different and are each integers of from 1 to
3. Non-limiting examples of such amines include
2-pentadecyl imidazoline; N-(2-aminoethyl) piperazine; and
mixtures thereof.
- Commercial mixtures of amine compounds may
advantageously be used. For example, one process for
preparing alkylene amines involves the reaction of an
alkylene dihalide (such as ethylene dichloride or propylene
dichloride) with ammonia, which results in a complex
mixture of alkylene amines wherein pairs of nitrogens are
joined by alkylene groups, forming such compounds as
diethylene triamine, triethylenetetramine, tetraethylene
-14- l 3 3 6 9 0 2
pentamine and corresponding piperazines. Low cost
poly(ethyleneamine) compounds averaging about S to 7
nitrogen atoms per molecule are available commerc-ially
under trade ~ar~s such as "Polyamine H", "Polyamine 400",
"Dow Polyamine E-100", etc.
Useful amines also include polyoxyalkylene
polyamines such as those of the formulae:
NH2 alkylene ~ 0-alkylene ~ 2 (III)
m
where m ha~ a value of about 3 to 70 and preferably 10 to
35; and
R ~ alkylene ~ O-alkylen ~ NH2)
n a (IV)
where "n" has a value of about l to 40, with the provision
that the sum of all the n's is from about 3 to about 70,
and preferably from about 6 to about 35, and R is a
substituted saturated hydrocarbon radical of up to lO
carbon atoms, wherein the number of substituents on the R
group is represented by the value of "a", which is a number
from 3 to 6. The alkylene groups in either formula (III)
or (IV) may be straight or branched chains containing about
2 to 7, and preferably about 2 to 4 carbon atoms.
The polyoxyalkylene polyamines of formulas (III)
or (IV) above, preferably polyoxyalkylene diamines and
polyoxyalkylene triamines, may have number average
molecular weights ranging from about 200 to about 4000 and
preferably from about 400 to about 2000. The preferred
polyoxyalkylene polyamines include the polyoxyethylene and
polyoxypropylene diamines and the polyoxypropylene tri-
amines having average molecular weights ranging from about
200 to 2000. The polyoxyalkylene polyamines are
commercially available and may be obtained, for example,
from the Jefferson Chemical Company, Inc. under the trade
m~rk "Jeffamine~ D-230, D-400, D-lOO0, D-2000, T-403n, etc.
1 336902
The amine is readily reacted with the dicarboxylic
acid material, e.g. alkenyl succinic anhydride, by heating
an oil solution containing 5 to 95 wt. % of dicarboxylic
acid material to about 100 to 200C., preferably lZ5 to
175C., generally for 1 to 10, e.g. 2 to 6 hours until the
desired amount of water is removed. The heating is
preferably carried out to favor formation of imides or
mixtures of imides and amides, rather than amides and
salts. Reaction ratios of dicarboxylic acid material to
equivalents of amine as well as the other nucleophilic
reactants described herein can vary considerably, depending
upon the reactants and type of bonds formed. Generally from
0.1 to 1.0, preferably about 0.2 to 0.6, e.g. 0.4 to 0.6,
moles of dicarboxylic acid moiety content (e.g. grafted
maleic anhydride content) is used, per equivalent of
nucleophilic reactant, e.g. amine. For example; about 0.8 _
mole of a pentamine (having two primary amino groups and 5
equivalents of nitrogen per molecule) is preferably used to
convert into a mixture of amides and imides, the product
formed by reacting one mole of olefin with sufficient
maleic anhydride to add 1.6 moles of succinic anhydride
groups per mole of olefin, i.e. preferably the pentamine is
used in an amount sufficient to provide about 0.4 mole
(that is 1.6/[0.8 x 5] mole) of succinic anhydride moiety
per nitrogen equivalent of the amine.
Tris(hydroxymethyl) amino methane (THAM) can be
reacted with the aforesaid acid material to form amides,
imides or ester type additives as taught by U.K. Patent 984,409,
or to form oxazoline compounds and borated oxazoline
compounds as described, for example, in u.S. Patents
fi,l~,2,798; 4,116,~76 and 4,113,639.
The ashless dispersants may also be esters derived
from the aforesaid long chain hydrocarbon substituted
dicarboxylic acid material and from hydroxy compounds such
as monohydric and polyhydric alcohols or aromatic compounds
such as phenols and naphthols, etc. The polyhydric alcohols
-16- 1 3 3 6 9 0 2
are the most preferred hydroxy compound and preferably
contain from 2 to about 10 hydroxy radicals, for example,
ethylene glycol, diethylene glycol, triethylene glycol,
tetraethylene glycol, dipropylene glycol, and other
alkylene glycols in which the alkylene radical contains
from 2 to about 8 carbon atoms. Other useful polyhydric
alcohols include glycerol, mono-oleate of glycerol,
monostearate of glycerol, monomethyl ether of glycerol,
pentaerythritol, dipentaerythritol, and mixtures thereof.
The ester dispersant may also be derived from
unsaturated alcohols such as allyl alcohol, cinnamyl
alcohol, propargyl alcohol, l-cyclohexane-3-ol, and oleyl
alcohol. Still other classes of the alcohols capable of
yielding the esters of this invention comprise the
ether-alcohols and amino-alcohols including, f~r example,
the oxy-alkylene, oxy-arylene-, amino-alkylene-, and
amino-arylene-substituted alcohols having one or more
oxy-alkylene, amino-alkylene or amino-arylene oxy-arylene
radicals. They are exemplified by Cellosolve, Carbitol,
N,N,N',N'-tetrahydroxy-trimethylene di-amine, and
ether-alcohols having up to about lSO oxy-alkylene radicals
in which the alkylene radical contains from 1 to about 8
carbon atoms.
The ester dispersant may be di-esters of succinic
acids or acidic esters, i.e., partially esterified succinic
acids; as well as partially esterified polyhydric alcohols
or phenol~, i.e., esters having free alcohols or phenolic
hydroxyl radicals. Mixtures of the above illustrated
esters likewise are contemplated within the scope of this
invention.
The ester dispersant may be prepared by one of
several known methods as illustrated for example in U.S.
Patent 3,381,022. The ester dispersant may also be
borated, similar to the nitrogen containing dispersants, as
described above.
*Trade mark
-17- l 3 3 6 9 0 2
Hydroxyamines which can be reacted with the
a~oreaaid long chain hydrocarbon substituted dicarboxylic
ac id mate rial to form dispe rsants include
2-amino-l-butanol, 2-amino-2-methyl-l-propanol,
p-(beta-hydroxyethyl)-aniline, 2-amino-1-propanol,
3-amino-l-propanol, 2-amino-2-methyl-1,3-propane-diol,
2-amino-2-ethyl-1,3-propanediol, N-(beta-hy-
droxypropyl)-N'-(beta-amino-ethyl)-piperazine,
tris(hydroxymethyl) amino-methane (also known as
trismethylolaminomethane) , 2-amino-l-butanol,
ethanolamine, beta-(beta-hydroxyethoxy)-ethylamine, and the
like. Mixtures of these or similar amines can also be
employed. The above description of nucleophilic reactants
suitable for reaction with the hydrocarbyl substituted
dicarboxylic acid or anhydride includes amines, alcohola,
and compounds of mixed amine and hydroxy containing
reactive functional groups, i.e.amino-alcohols.
A preferred group of ashless dispersants are those
derived from polyisobutylene substituted with succinic
anhydride groups and reacted with polyethylene amines,
e.g. tetraethylene pentamine, pentaethylene hexamine,
polyoxyethylene and polyoxypropylene amines, e.g.
polyoxypropylene diamine, trismethylolaminomethane and
pentaerythritol, and combinations thereof. One
particularly preferred dispersant combination involves a
combination of (A) polyisobutene substituted with succinic
anhydride groupa and reacted with (B) a hydroxy compound,
e.g. pentaerythritol, (C) a polyoxyalkylene polyamine,
e.g. polyoxypropylene diamine, and (D) a polyalkylene
polyamine, e.g. polyethylene diamine and tetraethylene
pentamine using about 0.3 to about 2 moles each of (B) and
(D) and about 0.3 to about 2 moles of (C) per mole of (A)
as described in U.S. Patent 3,804,763. Another preferred
dispersant combination involves the combination of (A)
polyisobutenyl succinic anhydride with (B) a polyalkylene
polyamine, e.g. tetraethylene pentamine, and (C) a
-18- 1 336902
polyhydric alcohol or polyhydroxy-substituted aliphatic
p r i m a r y a m i n e , e . g . , p e n t a e r y t h r i t o 1 o r
trismethylolaminomethane as described in U.S. Pat~ent
3,632,511.
A~(ii) Also useful as ashless nitrogen-containing
dispersant in this invention are dispersants wherein a
nitrogen containing polyamine is attached directly to the
long chain aliphatic hydrocarbon as shown in U.S. Patents
3,275,554 and 3,565,804 where the halogen group on the
halogenated hydrocarbon is displaced with various alkylene
polyamines.
A(iii) Another class of nitrogen containing
dispersants which may be used are those cont~ g Mannich
base or Mannich condensation products as they are known in
the art. Such Mannich condensation products generally are
prepared by condensing about 1 mole of a high molecular
weight hydrocarbyl substituted mono-or polyhydroxy benzene
(e.g., having a number average molecular weight of 1,000 or
greater) with about 1 to 2.5 moles of formaldehyde or
paraformaldehyde and about 0.5 to 2 moles polyalkylene
polyamine as disclosed, e.g., in U.S. Patents 3,442,808;
3,649,229 and 3,798,165. Such
Mannich condensation products may include a long chain,
high molecular weight hydrocarbon on the phenol group or
may be reacted with a compound containing such a
hydrocarbon, e.g., polyalkenyl succinic anhydride as shown
in said aforementioned U.S. Patent 3,442,808.
The ashless dispersants should be free of
boron-substitution so as to provide a fully formulated
oleaginous compo~3ition which is substantially free of
boron.
ComPonent B - Friction Modifiers
The lubricating oil friction modifier additive
comprise a friction modifying effective amount of at least
one alcohol ester or hydroxyamide derivative of a
1 336902
_ i
-19-
carboxylic acid having a total of from 24 to go carbon
atoms and at least 2, e.g., about 2 to 3, carboxylic acid
group~ per molecule. These ester friction modifier
additives are generally derived from the esterification of
a polycarboxylic acid with a di- or trihydric alcohol
(e.g., glycol, glycerol, oxa-alkane diols). Such esters
have been heretofore used in lubricating oils as friction
modifiers, and the methods of preparation thereof, and
structures, are described in U.S. Patents 3,429,817;
4,459,223; 4,479,883; 4,617,026; and 4,683,069-.
The hydroxyamide derivatives of such
polycarboxylic acids can be prepared by condensing the acid
at elevated temperature with a hydroxyamine (e.g. alkanol
amines or aminoalochols, such as ethanolamine,
diethanol-amine, propanolamine, 3-amino-1,1-propanediol),
employing the methods disclosed in U.S. Patent 4,557,846.
The carboxylic acid may be an aliphatic saturated
or unsaturated acid and will generally have a total of
about 24 to 90, preferably about 24 to 6~, carbon atoms and
at least 2, e.g., about 2 to 3, preferably about 2,
carboxylic acid ~ou~ with at least about 9 carbon atoms,
preferably about 12 to 42, especially 16 to 22 carbon atoms
between the carboxylic acid groups. Exemplary of the
hydroxyamide compatibilizers are oil soluble hydroxyamide
compounds having the formula:
J~ 3N(H)n2(Z)n3 ~ n4 (V)
wherein J1 is the hydrocarbon radical or skeleton of a
dimer carboxylic acid having a total of about 24 to about
90 carbon atoms with about 9 to about 42 carbon atoms
between carboxylic acid groups; Z is (a) a hydroxy
substituted alkyl group having about 1 to about 20 carbon
atoms, or (b) an oxyalkylene group of the formula:
1 336902
(CH- CHO)ns- H (VI)
wher- A and E are each alkyl of 1 to 2 carbon atoms or
hydrogen and n5 is an integer of 1 to 50; n2 is 0 or 1;
n3 is 1 or 2 and n4 i~ 1 or 2.
Preferred friction modifiers comprise partial
esters or diesters of dicarboxylic acids of the formulas:
HO-J'-OOC-J-COOH (VII), and
HO-J'-OOC-J-COOJ n -OH (VIII)
wherein J is the hydrocarbon radical of the acid and J' and
J" i~ either the hydrocarbon radical of an alkane diol or
the oxy-alkylene radical from an oxa-alkane diol as defined
hereinbelow. Generally about 1-3 moles of glycol,
preferably 1-2 moles of glycol, are used per mole of acid
to provide either a complete or partial ester.
Also, esters can be obtained by estérifying a
dicarboxylic acid or mixture of such acid~ with a mixture
of diols, in which case J would then be the hydrocarbon
radical of the dicarboxylic acid(s) and J' and J" would be
the hydrocarbon radicals associated with the diols.
The friction modifier additives are typically used
in the lubricating oil composition in an amount of from
about 0.0005 to 2, more preferably from about 0.001 to
0.25, and most preferably from about 0.005 to O.l, weight
percent.
Especially preferred friction modifier additives
are the dimer acid esters. The term dimer acid used herein
is moant to refer to those substituted cyclohexene
dicarboxylic acids formed by a Diels-Alder-type reaction
(whiçh is a thermal condensation) of C18-C22
unsaturated fatty acids, such as tall oil fatty acids,
which typically contain about 85 to 90 percent oleic or
linoleic acids. Such dimer acids typically contain about
36 carbon atoms. The dimer acid structure can be
generalized as follows:
1 336902
R2
R4 (IX)
R5
with two of the R2-R5 groups being carboxyl groups and
two being hydrocarbon groups depending upon how the
condensation of the carboxylic acid has occurred. The
ca rb oxyl g roup g can be - (C H 2 ) 8 C O O H ;
-CH=CH ( CH2 ) 8 COOH; - ( CH2 ) 7 COOH;
-CH2 -CH=CH ( CH2 ) 7 COOH; -CH=CH ( CH2 ) 7COOH and the
hydrocarbon terminating group can be represented by:
CH3 ( CH2 ) 4 -; CH3 ( CH2 ) 5 -; CH3 ( CH2 ) 7 -;
CH3 ( CH2 ) 4 CH=CH-: CH3 ( CH2 ) 4CH=CHCH2-, and the
like. The dimer of linoleic acid which is the, preferred
embodiment can be expressed in the following formula:
(CH2) 7COOH
H=CH ( CH2 ) 7 COOH
~I 1 (X)
( CH2 ) 5CH3
( CH2 ) 5CH3
Also the term dimer acid as used herein
necessarily includes products containing trimers (and
higher homologues), e.g., up to about 24 percent by weight
trimer, but more typically about 10 percent by weight
trimer since, as is well known in the art, the dimerization
reaction provides a product containing a trimer acid having
molecular weight of about three times the molecular weight
to the starting fatty acid.
The polycarboxylic acids or dimer acids noted
above are esterified with a glycol, the glycol being an
alkane diol or oxa-alkane diol represented by the formula
HO (R6CHCH20)xlH wherein R6 is H or CH3 and xl
is about 1 to 100, preferably 1 to 25 with ethylene glycol
and diethylene glycol particularly preferred. A preferred
1 336902
-22-
embodiment i5 formation of the ester with about 1 to 2
moles of glycol per mole of dimer acid or polycarboxylic
acid, such as the ester of diethylene glycol with dime~ized
linoleic acid. Illustrative of such esters are compounds
of the formula (XVI):
(CH2)7-D
H=cH(cH2)7-D
(XI)
¦ (CH2)scH3
(CH2)5cH3
wherein D is -~(0-CH2CH2)xl-OH, xl is as defined
above.
The preparation and use of the foregoing
polycarboxylic acid glycol esters as friction reducing
esters (viz., friction modifiers) is disclosed in U.S.
Patent 4,505,829,
Component C - CoPPer Antioxidant
The antioxidants useful in this invention include
oil soluble copper compounds. The copper antioxidants used
in the present invention are non-overbased, that is, the
selected compound is not overbased with carbon dioxide
under conditions sufficient to form a copper-metal,
carbonate-containing compound or complex. Therefore, the
copper antioxidants are preferably characterized by a total
base number (ASTM D2896) of less than 50, and most
preferably less than 20.
The copper may be blended into the oil as any
suitable oil soluble copper compound. By oil soluble we
mean the compound is oil soluble under normal blending
conditions in the oil or additive package. The copper
-23- ~ 3 3 6 9 0 2
compound may be in the cuprous or cupric form. The copper may
be in the form of the copper dihydrocarbyl thio- or dithio-
phosphates wherein copper may be substituted for zinc in the
anti-wear compounds and reactions described below although one
mole of cuprous or cupric oxide may be reacted with one or two
moles of the dithiophosphoric acid, respectively.
Also useful are oil soluble copper dithiocarbamates
of the general formula (R3lR32NCSS)nCu, where n is 1 or 2 and R3
and R32 are the same or different hydrocarbyl radicals
containing from 1 to 18 and preferably 2 to 12 carbon atoms and
including radicals such as alkyl, alkenyl, aryl, aralkyl, alkaryl
and cycloaliphatic radicals. Particularly preferred as R3l and
R32 groups are alkyl groups of 2 to 8 carbon atoms. Thus, the
radicals may, for example, be ethyl, n-propyl, i-propyl, n-butyl,
i-butyl, sec-butyl, amyl, n-hexyl, i-hexyl, n-heptyl, n-octyl ,
decyl, dodecyl, octadecyl, 2-ethylhexyl, phenyl, butylphenyl,
cyclohexyl, methylcyclopentyl, propenyl, butenyl, etc. In order
to obtain oil solubility, the total number of carbon atoms (i.e.,
R3l and R32) will generally be about 5 or greater. Copper
sulphonates, phenates, and acetylacetonates may also be used.
A further example of useful copper antioxidants are oil
soluble copper carboxylate compounds. The copper carboxylate
compound may be added in the cuprous or cupric form, and can
comprise a copper monocarboxylate or polycarboxylate, e.g.,
dicarboxylate, wherein the carboxylate moiety is derived from a
monocarboxylic acid or polycarboxylic acid, e.g., dicarboxylic
acid, of the formula:
R7 - CO2H (XII)
HO2CRaCO2H (XIII)
wherein R7 is selected from the group consisting of
-24- l 3 3 6 9 0 2
alkyl, alkenyl, aryl, alkaryl, aralkyl and cycloalkyl, and
wherein R3 is selected from the group consisting of alkylene,
alkenylene, arylene, alkarylene and aralkylene. Generally, acids
XII and XIII will have at least about 6 to about 35 carbon atoms,
and more usually from about 12 to about 24 carbon atoms, and more
usually from about 18 to 20 carbon atoms.
Exemplary of alkyl R7 groups are alkyls of from 5 to 34
carbon atoms, preferably 11 to 23 carbon atoms, and can be
branched or straight chained, e.g., heptyl, octyl, nonyl, decyl,
undecyl, dodecyl, tridecyl, tetradecyl, hexadecyl, octadecyl, 2-
methylhexyl, 3,5-ethyloctyl, polybutylenes, polypropylene andthe
like. When R7 is aryl, the aryl group will generally contain
from about 6 to 20 carbon atoms, e.g., phenyl, naphthyl and the
like. When R7 is alkaryl, each above aryl group can be
substituted by alkyl groups, which can be branched or straight
chained, and the total carbon atoms in such alkaryl groups will
generally contain from about 7 to 34, preferably 11 to 23, carbon
atoms. Illustrative of such alkaryl groups are
-Ar(CH3), -Ar(C2H5), -Ar(CgH19),
-Ar(C4Hg)2, - Ar(CH3)2, -Ar(C1OH21), and the like, wherein "Ar" is
a phenyl ring. When R7 is alkenyl, the alkenyl group will
generally contain from 5 to 34 carbon atoms, e.g., hexenyl,
heptenyl, octenyl, dodecenyl, octadecenyl, and the like. When
R7 is aralkyl, the alkyl group, which can be branched or straight
chained, can contain from 1 to 28 carbon atoms, and can be
substituted by from 1 to 3 (e.g., 1 or 2) aryl groups, such as
those described above (e.g., phenyl). Examples of such aralkyl
groups are ArCH2-, ArC2H4-, ArC8H16-, ArCgHl8-,CH3CH(Ar)C6H12-, and
the like. When R7 is cycloalkyl, the cycloalkyl group will
generally contain from about 3 to 18 carbon atoms, e.g.,
cyclohexyl, cycloheptyl, cyclooctyl, cyclodecyl, cyclododecyl and
the like.
F~
.
1 336902
Examples of monocarboxylic acids of formula XII are
oleic acid, dodecanoic acid, naphthenic acid, linoleic acid,
linolenic acid, cyclohexane carboxylic acid, phenyl acetic acid,
benzoic acid, stearic acid, palmitic acid, myristic acid, lauric
acid, and the like.
Exemplary of R8 groups are straight chain alkylene of
from 2 to 33 carbon atoms, e.g., -(CH2)X-, wherein x is an
integer of from 2 to 33, and branched chain alkylenes of from 4
to 33 carbon atoms, e.g., -CH2-, -C2H4-, -C3H6-, -C8Hl6-, -Clo-H20-
-Cl2H24-, -Cl4H28-, and the like. When R3 is alkenylene, the R5
group will generally contain from 4 to 33 carbon atoms, e.g., -CH
= C2H3-, -CH2CH = CHC4H8- and the like. When R8 is arylene, the
arylene group will generally contain from 6 to 20 carbon atoms,
e.g., phenylene, naphthylene, and the like. The arylene groups
may be alkyl substituted by from 1 to 14 carbon atoms. Exemplary
of such alkarylene groups are -Ar(CH3)-, -Ar(C2H5)-, -Ar(CH3) 2 - ~
-Ar(CH3)3-, and the like, wherein "Ar" is a phenyl ring. When R8
is aralkylene, the alkylene groups as described above, can be
substituted by one or more (e.g., 1-3) aryl groups, e.g., phenyl.
Examples of such dicarboxylic acids are phthalic acid,
iso- and tere- phthalic acids, suberic acid, azelaic acid,
sebacic acid, decanedioic acid, dodecanedioic acid, penta-,
hepta-, hexa- and octa- decane dioic acids, and the like. Also
exemplary are branched carboxylic acids such as napthenic acids
of molecular weight from 200 to 500 or synthetic carboxylic
acids.
The carbon atoms of the hydrocarbyl moieties of the
acids of formula XII and XIII can be optionally substituted by
an inert substituent, that is, a substituent which does not
interfere with the acid-copper salt formation reaction, and which
does not adversely affect the antioxidant effect of the copper
carboxylate compound.
~''
1~`
-26- l 3 3 6 9 0 2
Suitable such inert substituents include halide (e.g., C1, Br),
hydroxy, thio, amido, imido, cyano, thiocyano, isothiocyano,
keto, carbalkoxy and the like. Preferably, the copper
carboxylate is derived from alkanoic and alkenoic monocarboxylic
acids of from 8 to 35 carbon atoms or saturated or unsaturated
fatty dicarboxylic acids of from 8 to 35 carbon atoms.
Especially preferred are copper salts of alkanoic monocarboxylic
acids of from 12 to 24 carbon atoms containing s3 branches per
chain, such as copper octanoate, copper oleate, copper
dodecanoate, and the like. Examples include C10 to C18 fatty
acids such as stearic or palmitic, but unsaturated acids such as
oleic or branched carboxylic acids such as napthenic acids of
molecular weight from 200 to 500 or synthetic carboxylic acids
are preferred because of the improved handling and solubility
properties of the resulting copper carboxylates.
Also exemplary of useful copper compounds are copper
(CuI and/or CuII) salts of alkenyl succinic acids or anhydrides.
The salts themselves may be basic, neutral or acidic. They may
be formed by reacting (a) any of the materials discussed above
in the Ashless Dispersant section, which have at least one free
carboxylic acid (or anhydride) group with (b) a reactive metal
compound. Suitable acid (or anhydride) reactive metal compounds
include those such as cupric or cuprous hydroxides, oxides,
acetates, borates, and carbonates or basic copper carbonate.
Examples of the metal salts of this invention are Cu
salts of polyisobutenyl succinic anhydride (hereinafter referred
to as CU-PIBSA), and Cu salts of polyisobutenyl succinic acid.
Preferably, the selected metal employed is its divalent form,
e.g., Cu+2. The preferred substrates are polyalkenyl succinic
acids in which the alkenyl group has a molecular weight greater
than about 700. The alkenyl group desirably has a Mn from about
900 to 1400, and up to 2500, with a ~n of about 950 being most
~'
-27- 1 3 3 6 9 0 2
pre~err-d. Especially preferred, of those listed above in
the section on Dlspersant~, is polyisobutylene succinic
acid (PIBSA). These materials may desirably be dissolved
in a solvent, such as a mineral oil, and heated in the
presence of a water solution (or slurry) of the metal
bearing material. Heating may take place between 70 and
about 200C. Temperatures of 110 to 140C are
entirely adequate. It may be necessary, depending upon the
salt produced, not to allow the reaction to remain at a
temperature above about 140C for an extended period of
time, e.g., longer than 5 hours, or decomposition of the
salt may occur.
The copper compounds useful as antioxidants herein
can be formed by conventional means. Thus the copper
carboxylate can be formed by contacting one or more of the
above carboxylic acids with a copper source, such as a
reactive inorganic or organic copper compound. Preferred
copper sources are copper oxide, copper acetate, copper
hydroxide, copper borate, copper carbonate, and the like.
The acid and copper source generally will be contacted for
reaction in the presence of a solvent or inert reaction
diluent, e.g., water or alcohol, for a time and at a
temperature sufficient to effect the desired reaction.
Generally, a time of from about 0.5 to 24 hrs. and a
temperature of from about 25 to 150-C will be suitable,
although contact times and temperatures out~ide of these
range~ can be employed, if desired.
While any effective amount of the copper
antioxidant can be incorporated into the lubricating oil
composition, it is contemplated that such effective amounts
be sufficient to provide said lube oil composition with an
amount of the copper antioxidant of from about 5 to 500
(more preferably 10 to 200, still more preferably 10 to
180, and most preferably 20 to 130 (e.g., 90 to 120)) part
per million of added copper based on the weight of the
lubricating oil composition. The amount of copper
-28- l 3 3 6 9 0 2
antioxidant in this range should be at least sufficient to
provide a B:Cu atomic ratio of from 0 to about 0.6:1,
preferably less than about 0.4:1, and most preferably less
than about 0.2:1. Of course, the preferred amount may
depend amongst other factors on the quality of the
basestock lubricating oil.
The copper antioxidants used in this invention are
inexpensive and are effective at low concentrations and
therefore do not add substantially to the cost of the
product. The results obtained are frequently better than
those obtained with previously used antioxidants, which are
expensive and used in higher concentrations. The copper
compounds can be utilized to replace part or all of the
need for supplementary antioxidants. Thus, for
particularly severe conditions it may be desirable to
include a supplementary, conventional antioxidant. However,
the amounts of supplementary antioxidant required are
small, far less than the amount required in the absence of
the copper compound.
The copper carboxylate can be formed by
conventional means, as by contacting one or more of the
above carboxylic acids with a copper source, such as a
reactive inorganic or organic copper compound. Preferred
copper sources are copper oxide, copper acetate, copper
hydroxide, copper borate, copper carbonate, and the like.
The acid and copper source generally will be contacted for
reaction in the presence of a solvent or inert reaction
diluent, e.g., water or alcohol, for a time and at a
temperature sufficient to effect the desired reaction.
Generally, a time of from about 0.5 to 24 hrs. and a
temperature, of from about 25 to 150C will be suitable,
although contact times and temperatures outside of these
ranges can be employed, if desired.
The copper antioxidants (e.g., Cu-oleate,
Cu-naphthanate, etc. will be generally employed in an
amount of from about 50-500 ppm by weight of the Cu metal,
-29- 1 33690~
in the final lubricating or fuel composition. The amount
of copper antioxidant in this range should be at least
sufficient to provide a B:Cu atomic ratio of from O to
about 0.6:1, preferably less than about 0.4:1, and most
preferably less than about 0.2:1.
_30_ 1 3 3 6 9 0 2
THE COMPOSITIONS
The additive mixtures of the present invention
possess very good storage stability and friction
modification properties as measured herein in a wide
variety of environments. Accordingly, the additive
mixtures are used by incorporation and dissolution into an
oleaginous material such as fuels and lubricating oils.
When the additive mixtures of this invention are
used in normally liquid petroleum fuels such as middle
distillates boiling from about 65 to 430C., including
kerosene, diesel fuels, home heating fuel oil, jet fuels,
etc., a concentration of the additive in the fuel in the
range of typically from about 0.001 to about 0.5, and
preferably 0.001 to about 0.1 weight percent, based on the
total weight of the composition, will usually be employed.
The additive mixtures of the present invention
find their primary utility in lubricating oil compositions
which employ a base oil in which the additives are
dissolved or dispersed. Such base oils may be natural or
synthetic. Base oils suitable for use in preparing the
lubricating oil compositions of the present invention
include those conventionally employed as crankcase
lubricating oils for spark-ignited and compression-ignited
internal combustion engines, such as automobile and truck
engines, marine and railroad diesel engines, and the like.
Advantageous results are also achieved by employing the
additive mixtures of the present invention in base oils
conventionally employed in and/or adapted for use as power
transmitting fluids such as automatic transmission fluids,
tractor fluids, universal tractor fluids and hydraulic
fluids, heavy duty hydraulic fluids, power steering fluids
and the like. Gear lubricants, industrial oils, pump oils
and other lubricating oil compositions can also benefit
from the incorporation therein of the additive mixtures of
the present invention.
-
1 336902
-31-
Thus, the additives of the present invention may
be suitably incorporated into synthetic base oils such as
alkyl esters of dicarboxylic acids, polyglycols and
alcohols; polyalpha-olefins, alkyl benzenes, organic esters
of phosphoric acids, polysilicone oil, etc.
Natural base oils include mineral lubricating oils
which may vary widely as to their crude source, e.g.
whether paraffinic, naphthenic, mixed, par-
affinic-naphthenic, and the like; as well as to their
formation, e.g., distillation range, straight run or
cracked, hydrofined, solvent extracted and the like.
More specifically, the natural lubricating oil
base stocks which can be used in the compositions of this
invention may be straight mineral lubricating oil or
distillates derived from paraffinic, naphthenic, asphaltic,
or mixed base crudes, or, if desired, various blended oils
may be employed as well as residuals, particularly those
from which asphaltic constituents have been removed. The
oils may be refined by conventional methods using acid,
alkali, and/or clay or other agents such as aluminum
chloride, or they may be extracted oils produced, for
example, by solvent extraction with solvents of the type of
phenol, sulfur dioxide, furfural, dichlorodiethyl ether,
nitrobenzene, crotonaldehyde, etc.
The lubricating oil base stock conveniently has a
viscosity of typically about 2.5 to about 12, and
preferably about 2.5 to about 9 cst. at 100C.
Thus, the additive mixtures of this invention,
that is the non-borated ashless dispersant, friction
modifier and copper antioxidants, can be employed in a
lubricating oil composition which comprises lubricating
oil, typically in a major amount, and the additive mixture,
typically in a minor amount, which is effective to impart
enhanced dispersancy, rust inhibition and oxidation
inhibition, relative to the absence of the additive
mixture. Additional conventional additives selected to
-32- 1 3 3 6 9 0 2
meet the particular requirements of a selected type of
lubricating oil composition can be included as desired.
The ashless dispersants, friction modifiers and
copper antioxidants employed in this invention are
oil-soluble, dissolvable in oil with the aid of a suitable
solvent, or are stably dispersible materials. Oil-soluble,
dissolvable, or stably dispersible as that terminology is
used herein does not necessarily indicate that the
materials are soluble, dissolvable, miscible, or capable of
being suspended in oil in all proportions. It does mean,
however, that the additives, for instance, are soluble or
stably dispersible in oil to an extent sufficient to exert
their intended effect in the environment in which the oil
is employed. Moreover, the additional incorporation of
other additives may also permit incorporation of higher
levels of a particular dispersant, friction modifier,
and/or copper antioxidant, if desired.
Accordingly, while any effective amount of the
additive mixture can be incorporated into the lubricating
oil composition, it is contemplated that such effective
amount be sufficient to provide said lube oil composition
with an amount of the additive of typically from about 0.01
to about 10 (e.g., 0.1 to 8), and preferably from about 0.2
to about 6 weight percent of the additive mixtures of this
invention based on the weight of the active ashless
dispersant, copper carboxylate antioxidant and friction
modifier in said composition.
Preferably, the additive mixtures of this
invention, and the components thereof, are used in an
amount sufficient to provide fully formulated lubricating
oil compositions containing from about 5 to 500 ppm oil
soluble copper antioxidant compound (calculated as Cu
metal), from about 0.01to about 5 wt. % friction modifier
compound, and from about 1 to 8 wt. % of ashless
dispersant, which is substantially free of boron as
described above.
~33~ 1 336902
The additives of the present invention can be
incorporated into the lubricating oil in any convenient
way. ThUs, they can be added directly to the oil by
dispersing, or dissolving the same in the oil at the
desired level of concentration. Such blending can occur at
room temperature or elevated temperatures (e.g., at 70 to
130C). Alternatively, the additive~ may be blended with
a suitable oil-soluble solvent and base oil to form a
concentrate (e.g., "adpacksn) , and then the concentrate
may be blended with lubricating oil base stock to obtain
the final formulation. Such concentrates will typically
contain (on an active ingredient (A.I.) basis) from about 3
to about 45 wt. %, and preferably from about`10 to about 35
wt. %, ashless dispersant additive A; from about 0.005 to 2
wt. %, typically from about 0.001 to 0.25 wt. %, and
preferably from about 0.005 to 0.1 wt. ~ friction modifier
additive B; typically from about 0.005 to 1.0 wt. %,
preferably from about 0.05 to 0.2 wt. %, copper antioxidant
additive C (expressed as ppm by weight of added copper in the
concentrate); and typically from about 30 to 90 wt. %,
preferably from about 40 to 60 wt. %, base oil, based on the
concentrate weight.
Such concentrates will typically contain from
about 20 to about 80%, and preferably from about 25 to
about 65%, by weight total active additive (that is,
ashless dispersant, friction modifier, copper antioxidant
and any other added additive, described below), and
typically from about 80 to about 20%, preferably from about
to about 20% by weight base oil, based on the
concentrate weight. Where present, for example, metal
detergents will be typically present in such concentrates
in an amount of from about from about 2 to 45 wt.~, and
preferably from about 2 to 14 wt.%.
The lubricating oil base stock for the additives
of the present invention typically is adapted to perform a
selected function by the incorportion of additives therein
to form lubricating oil compositions (i.e., formulations).
. ~34~ 1 3 3 6 9 0 2
Representative additional additives typically
present in such formulations include viscosity modifiers,
corrosion inhibitors, other oxidation inhibitors, friction
modifiers, anti-foaming agents, anti-wear agents, pour
point depressants, detergents, metal rust inhibitors and
the like.
The compositions of this invention can also be
used with viscosity index (V.I.) improvers to form
multi-grade automotive engine lubricating oils. Viscosity
modifiers impart high and low temperature operability to
the lubricating oil and permit it to remain relatively
viscous at elevated temperatures and also exhibit
acceptable viscosity or fluidity at low temperatures.
Viscosity modifiers are generally high molecular weight
hydrocarbon polymers including polyesters. The viscosity
modifiers may also be derivatized to include other
properties or functions, such as the addition of
dispersancy properties. These oil soluble viscosity
modifying polymers will generally have number average
molecular weights of from 103 to 1o6, preferably 104 to
106, e.g., 20,000 to 250,000, as determined by gel
permeation chromatography or osmometry.
Examples of suitable hydrocarbon polymers include
homopolymers and copolymers of two or more monomers of C2
to C30, e.g., C2 to C8 olefins, including both alpha
olefin~ and internal olefins, which may be straight or
branched, aliphatic, aromatic, alkyl-aromatic,
cycloaliphatic, etc. Frequently they will be of ethylene
with C3 to C30 olefins, particularly preferred being
the copolymers of ethylene and propylene. Other polymers
can be used such as polyisobutylenes, homopolymers and
copolymers of C6 and higher alpha olefins, atactic
polypropylene, hydrogenated polymers and copolymers and
terpolymers of styrene, e.g. with isoprene and/or butadiene
and hydrogenated derivatives thereof. The polymer may be
degraded in molecular weight, for example by mastication,
-35-
- 1 336902
extrusion, oxidation or thermal degradation, and it may be
oxidized and contain oxygen. Also included are deriva-tized
polymers such as post-grafted interpolymers of
ethylene-propylene with an active monomer such as maleic
anhydride which may be further reacted with an alcohol, or
amine, e.g. an alkylene polyamine or hydroxy amine, e.g.
see U.S. Patent Nos. 4,089,794; 4,160,739; 4,137,185; or
copolymers of ethylene and propylene reacted or grafted
with nitrogen compounds such as shown in U.S. Patent Nos.
4,068,056; 4,068,058; 4,146,489 and 4,149,984.
The preferred hydrocarbon polymers are ethylene
copolymers containing from 15 to 90 wt. % ethylene,
preferably 30 to 80 wt. % of ethylene and 10 to 85 wt. %,
preferably 20 to 70 wt. % of one or more ~3 to C28,-
preferably C3 to C18, more preferably C3 to C8,
alpha-olefins. While not essential, such copolymers
preferably have a degree of crystallinity of less than 25
wt. %, as determined by X-ray and differential scanning
calorimetry. Copolymer~ of ethylene and propylene are most
preferred. Exemplary are the improved ethylene-propylene
copolymers disclosed in u.S. Patent 4, 804, 794 .
Other alpha-olefins suitable
in place of propylene to form the copolymer, or to be used
in combination with ethylene and propylene, to form a
terpolymer, tetrapolymer, etc., include l-butene,
l-pentene, l-hexene, l-heptene, l-octene, l-nonene,
l-decene, etc.; also branched chain alpha-olefins, such as
4-methyl-1-pentene, 4-methyl-1-hexene, 5-methylpentene-1,
4,4-dimethyl-1-pentene, and 6-methylheptene-1, etc., and
mixtures thereof.
- Terpolymers, tetrapolymer~, etc., of ethylene,
said C3_28 alpha-olefin, and a non-conjugated diolefin or
mixtures of such diolefins may also be used. The amount of
the non-conjugated diolefin generally ranges from about 0.5
to 20 mole percent, preferably from about 1 to about 7 mole -
1 336902
-36-
percent, based on the total amount of ethylene and
alpha-olefin present.
The polyester V.I. improvers are generally
polymers of esters of ethylenically unsaturated C3 to
C8 mono- and dicarboxylic acids such as methacrylic and
acrylic acids, maleic acid, maleic anhydride, fumaric acid,
etc.
Example~ of unsaturated esters that may be used
include those of aliphatic saturated mono alcohols of at
least 1 carbon atom and preferably of from 12 to 20 carbon
atoms, such as decyl acrylate, lauryl acrylate, stearyl
acrylate, eicosanyl acrylate, docosanyl acrylate, decyl
methacrylate, diamyl fumarate, lauryl methacrylate, cetyl
methacrylate, stearyl methacrylate, and the like and
mixtures thereof.
Other esters include the vinyl alcohol esters of
C2 to C22 fatty or mono carboxylic acids, preferably
saturated such as vinyl acetate, vinyl laurate, vinyl
palmitate, vinyl stearate, vinyl oleate, and the like and
mixtures thereof. Copolymers of vinyl alcohol esters with
unsaturated acid esters such as the copolymer of vinyl
acetate with dialkyl fumarates, can also be used.
The esters may be copolymerized with still other
unsaturated monomers such as olefins, e.g. 0.2 to 5 moles
f C2 ~ C20 aliphatic or aromatic olefin per mole of
unsaturated e~ter, or per mole of unsaturated acid or
anhydride followed by esterification. For example,
copolymers of styrene with maleic anhydride esterified with
alcohols and amines are known, e.g., see U.S. Patent
3,702,300.
Such ester polymers may be grafted with, or the
ester copolymerized with, polymerizable unsaturated
nitrogen-containing monomers to impart dispersancy to the
V.I. improvers. Examples of suitable unsaturated
nitrogen-containing monomers include those containing 4 to
20 carbon atoms such as amino substituted olefins as
1 3369Q2
p- (beta-diethylaminoethyl ) styrene; bas ic
nitrogen-containing heterocycles carrying a polymerizable
ethylenically unsaturated substituent, e.g. the vinyl
pyridines and the vinyl alkyl pyridine~ such as
2-vinyl-5-ethyl pyridine, 2-methyl-S-vinyl pyridine,
2-vinyl-pyridine, 3-vinyl-pyridine,
4-vinyl-pyridine, 3-methyl-5-vinyl-pyridine,
4-methyl-2-vinyl-pyridine, 4-ethyl-2-vinyl-pyridine and
2 -butyl-5 -vinyl -pyridine and the 1 ike .
N-vinyl lactams are also suitable , e . g ., N-vinyl
pyrrolidones or N-vinyl piperidones.
The vinyl pyrrolidones are preferred and are
exemplified by N-vinyl pyrrolidone, N-(l-methylvinyl)
pyrrol idone, N-vinyl-s-methyl pyrrolidone,
N-viny1-3, 3-dimethy1pyrro1idone, N-viny1-5-ethy1
pyrrolidone, and the like.
Corrosion inhibitors, also known as anti-corrosive
agents, reduce the degradation of the metall ic parts
contacted by the lubricating oil composition. Illustrative
of corrosion inhibitors are phosphosulfurized hydrocarbons
and the products obta ined by reaction of a phos-
phosulfurized hydrocarbon with an alkaline earth metal
oxide or hydroxide, preferably in the presence of an
alkylated phenol or of an alkylphenol thioester, and also
preferably in the presence of carbon dioxide.
Phosphosulfurized hydrocarbons are prepared by reacting a
suitable hydrocarbon such as a terpene, a heavy petroleum
fraction of a C2 to C6 olefin polymer such as
polyisobutylene, with from 5 to 30 weight percent of a
sulfide of phosphorus for 1/2 to 15 hours, at a temperature
in the range of 65 to 315C . Neutral ization of the
phosphosulfurized hydrocarbon may be effected in the manner
taught in U. S . Patent No. 1, 969, 324 .
Oxidation inhibitor~ reduce the tendency of
mineral oils to deteriorate in service which deterioration
can be evidenced by the products of oxidation such as
-- -38-
1 336902
sludgQ and varnish-like deposits on the metal surfaces and
by viscosity growth. Such oxidation inhibitors include
alkal~ne earth metal salts of alkylphenol-sulfides and
-thioesters having preferably C5 to C12 alkyl side
chains (e . g., calcium nonylphenol sulfide, barium
t-octylphenyl sulfide) , di(octylphenyl)amine,
phenyl-alpha-naphthylamine, phosphosulfurized or sulfurized
hydrocarbons, etc.
Friction modifiers serve to impart the proper
friction characteristics to lubricating oil compositions
such as automatic transmission fluids.
Representative examples of suitable supplemental
friction modifiers are found in U.S. Patent No. 3,933,659
which discloses fatty acid esters and amides; U.S. Patent
No. 4,176,074 which describes molybdenum complexes of
polyisobutenyl succinic anhydride-amino alkanols; U.S.
Patent No. 4,105,571 which discloses glycerol esters of
dimerized fatty acids; U.S. Patent No. 3,779,928 which
discloses alkane phosphonic acid salts; U.S. Patent No.
3, 778, 375 which discloses reaction products of a
phosphonate with an oleamide; U.S. Patent No. 3,852,205
which discloses S-carboxy-alkylene hydrocarbyl succinimide,
S-carboxyalkylene hydrocarbyl succinamic acid and mixtures
thereof; U.S. Patent No. 3,879,306 which discloses
N-(hydroxy-alkyl) alkenyl-succinamic acids or succinimides;
U.S. Patent No. 3,932,290 which discloses reaction products
of di-(lower alkyl) phosphites and epoxides; and U.S.
Patent No. 4,028,258 which discloses the alkylene oxide
adduct of phosphosulfurized N-(hydroxyalkyl) alkenyl
succinimides. Th~ most preferred
friction modifiers are succinate esters, or metal salts
thereof, of hydrocarbyl substituted succinic acids or
anhydrides and thiobis alkanols such as described in U.S.
Patent No. 4,344,853.
~39~ 1 3 3 6 9 0 2
Rust inhibitors useful in this invention comprise
nonionic surfactants such as polyoxyalkylene polyols and
esters thereof. Such anti-rust compounds are known and can
be made by conventional means. Nonionic surfactants,
useful as anti-rust additives in the oleaginous
compositions of this invention, usually owe their
surfactant properties to a number of weak stabilizing
groups such as ether linkages. Nonionic anti-rust agents
containing ether linkages can be made by alkoxylating
organic substrates containing active hydrogens with an
excess of the lower alkylene oxides (such as ethylene and
propylene oxides) until the desired number of alkoxy groups
have been placed in the molecule.
The preferred rust inhibitors are polyoxyalkylene
polyols and derivatives thereof. This class of materials ~
are commercially available from various sources: Pluronic*
Polyols from Wyandotte Chemicals Corporation; Polyglycol
112-2, a liquid triol derived from ethylene oxide and
propylene oxide available from Dow Chemical Co.; and
Tergitol*, dodecylphenyl or monophenyl polyethylene glycol
ethers, and Ucon* polyalkylene glycols and derivatives,
both available from Union Carbide Corp. These are but a
few of the commercial products suitable as rust inhibitors
in the improved composition of the present invention.
In addition to the polyols per se, the esters
thereo~ obtained by reacting the polyols with various
carboxylic acids are also suitable. Acids useful in
preparing these esters are lauric acid, stearic acid,
succinic ac id, and alkyl- or alkenyl-substituted succinic
acids wherein the alkyl-or alkenyl group contains up to
about twenty carbon atoms.
The preferred polyols are prepared as block
polymers. Thus, a hydroxy-substituted compound,
R8-(OH)n (wherein n8 is 1 to 6, and R8 is the
residue of a mono- or polyhydric alcohol, phenol, naphthol,
etc.) is reacted with propylene oxide to form a hydrophobic
*Trade mark
-40- 1 3 3 6 9 0 2
base. This base is then reacted with ethylene oxide to
provide a hydrophylic portion resulting in a molecule
having both hydrophobic and hydrophylic portions. The
relative sizes o~ these portions can be ad~usted by
regulating the ratio of reactants, time of reaction, etc.,
as i~ obvious to those skilled in the art. Thus it is
within the skill of the art to prepare polyols whose
molecules are characterized by hydrophobic and hydrophylic
moieties which are present in a ratio rendering rust
inhibitors suitable for use in any lubricant composition
regardless of differences in the base oils and the presence
of other additives.
If more oil-solubility is needed in a given
lubricating composition, the hydrophobic portion can be
increased and/or the hydrophilic portion decreased. If
greater oil-in-water emulsion breaking ability is required,
the hydrophilic and/or hydrophobic portions can be adjusted
to accomplish this.
Compounds illustrative of R-(OH)n include
alkylene polyols such as the alkylene glycols, alkylene
triols, alkylene tetraols, etc., such as ethylene glycol,
propylene glycol, glycerol, pentaerythritol, sorbitol,
mannitol, and the like. Aromatic hydroxy compounds such as
alkylated mono- and polyhydric phenols and naphthols can
also be used, e.g., heptylphenol, dodecylphenol, etc.
Other suitable demulsifiers include the esters
disclo~d in U.S. Patentq 3,098,827 and 2,674,619.
The liquid polyols available from Wyandotte
Chemical Co. under the name Pluronic Polyols and other
similar polyols are particularly well suited as rust
inhibitors. These Pluronic Polyols correspond to the
formula (XIV):
HO (CH2CH2O)x(lHcH2o)y(cH2cH2o)z-H
CH3
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1 336902 - ^
wherein x, y, and z are integers greater than 1 such that
the CH2CH2O groups comprise from ab~ut 10% to about 40%
by weight of the total molecular weight of the glycol, the
average molecular weight of said glycol being from about
1000 to about 5000.
These products are prepared by first condensing
propylene oxide with propylene glycol to produce the
hydrophobic base
HO(-ICH~CH2~0)y~H (XV)
CH3
This condensation product is then treated -with ethylene
oxide to add hydrophylic portions to both ends of the
molecule. For best results, the ethylene oxide units
should comprise from about 10 to about 40% by weight of the
molecule. Those products wherein the molecular weight of
the polyol is from about 2500 to 4500 and the ethylene
oxide units comprise from about 10% to about 15% by weight
of the molecule are particularly suitable. The polyols
having a molecular weight of about 4000 with about 10%
attributable to (CH2CH20) units are particularly good.
Also useful are alkoxylated fatty amines, amides, alcohols
and the like, including such alkoxylated fatty acid
derivatives treated with Cg to C16 alkyl-substituted
phenols (such as the mono- and di-heptyl, octyl~ nonyl,
decyl, undecyl, dodecyl and tridecyl phenols), as descri~ed
in U.S. Patent 3,849,501.
Pour point depressants lower the temperature at
which the fluid will flow or can be poured. Such
depressants are well known. Typical of those additives
which usefully optimize the low temperature fluidity of the
fluid are C8-C18 dialkylfumarate vinyl acetate
copolymers, polymethacrylates, and wax naphthalene.
-42- 1 3 3 6 9 G 2
Foam control can be provided by an antifoamant of
the polysiloxane type, e.g. silicone oil and polydimethyl
siloxane.
Anti-wear agents, as their name implies, reduce
wear of metal parts. Representative of conventional
anti-wear agents are zinc dihydrocarbyldithiophosphates,
e.g., wherein the hydrocarbyl groups are the same or
different and are Cl to C18 (preferably C2 to C12)
alkyl, alkenyl, aryl, alkaryl, aralkyl and cycloalkyl.
Detergents and metal rust inhibitors include the
metal salts of sulphonic acids, alkyl phenols, sulfurized
alkyl phenols, alkyl salicylates, naphthenates and other
oil soluble mono- and di-carboxylic acid~. Highly basic
(that is, overbased) metal salts, such as highly basic
alkaline earth metal sulfonates (especially Ca and Mg
salts) are frequently used as detergents.
The highly basic alkaline earth metal sulfonates
are usually produced by heating a mixture comprising an
oil-soluble alkaryl sulfonic acid with an excess of
alkaline earth metal compound above that required for
complete neutralization of the sulfonic and thereafter
forming a dispersed carbonate complex by reacting the
excess metal with carbon dioxide to provide the desired
overbasing. The sulfonic acids are typically obtained by
the sulfonation of alkyl substituted aromatic hydrocarbons
such a~ those obtained from the fractionation of petroleum
by di~tillation and/or extraction or by the alkylation of
aromatic hydrocarbons as, for example, those obtained by
alkylating benzene, toluene, xylene, naphthalene, diphenyl
and the halogen derivatives such as chlorobenzene,
chlorotoluene and chloronaphthalene. The alkylation may be
carried out in the presence of a catalyst with alkylating
agents having from about 3 to more than 30 carbon atoms
such as, for example, haloparaffins, olefins that may be
obtained by dehydrogenation of paraffins, polyolefins as,
for example, polymers from ethylene, propylene, etc. The
1 3369û2
-43-
alkaryl sulfonates usually contain from about 9 to about 70
or more carbon atoms, preferably from about 16 to about 50
carbon atoms per alkyl substituted aromatic moiety.
The alkaline earth metal compounds which may be
used in neutralizing these alkaryl sulfonic acids to
provide the sulfonates includes the oxides and hydroxides,
alkoxidee, carbonates, carboxylate, sulfide, hydrosulfide,
nitrate, borates and ethers of magnesium, calcium, and
barium. Examples of calcium oxide, calcium hydroxide,
magnesium acetate and magnesium borate. As noted, the
alkaline earth metal compound is used in excess of that
required to complete neutralization of the alkaryl sulfonic
acids. Generally, the amount ranges from about 100 to
220%, although it is preferred to use at least 125% of the
stoichiometric amount of metal required for complete--
neutralization.
The preparation of highly basic alkaline earth
metal alkaryl sulfonates are generally known as earlier
indicated such as in U.S. 3,150,088 and 3,150,089 wherein
overbasing is accomplished by hydrolysis of the
alkoxide-carbonate complex with the alkaryl sulfonate in a
hydrocarbon solvent-diluent oil. It is preferable to use
such a hydrocarbon solvent-diluent oil for the volatile
by-products can be readily removed leaving the rust
inhibitor additive in a carrier, e.g., Solvent 150N*
lubricating oil, suitable for blending into the lubricating
oil composition. For the purposes of this invention, a
pre~erred alkaline earth sulfonate is magnesium alkyl
aromatic sulfonate having a total base number (ASTM D2896)
ranging from about 300 to about 400 with the magnesium
sulfonate content ranging from about 25 to about 32 wt.
based upon the total weight of the additive system
dispersed in Solvent 150 Neutral Oil.
Polyvalent metal alkyl salicylate and naphthenate
materials are known additives for lubricating oil
compositions to improve their high temperature performance
*Trade mark
1 336902
-44-
and to counteract deposition of carbonaceous matter on
piston~ (U.S. Patent 2,744,069). An increase in reserve
ba icity of the polyvalent metal alkyl salicylates and
naphthenate~ can be realized by utilizing alkaline earth
metal, e.g., calcium, salts of mixtures of C8-C26 alkyl
salicylates and phenate~ (see U.S. Patent 2,744,069) or
polyvalent metal salts of alkyl salicylic acid~, said acids
obtained from the alkylation of phenols followed by
phenation, carboxylation and hydroly~is (U.S. Patent
3,704,315) which could then be converted into highly basic
salts by techniques generally known and used for such
conversion. The reserve basicity of the~e metal-containing
rust inhibitors is usefully at TBN levels of between about
60 and 150. Included with the useful polyv~lent metal
salicylate and napththenate materials are the methylene and
sulfur bridged materials which are readily derived from
alkyl substituted salicylic or naphthenic acid~ or mixtures
of either or both with alkyl substituted phenol~. Basic
sulfurized salicylates and a method for their preparation
is shown in U.S. Patent 3,595,791.
Fo r p u rp ose s o f th is disclosure the
salicylate/naphthenate rust inhibitors are the alkaline
earth (particularly magnesium, calcium, strontium and
barium) salts of the aromatic acids having the general
formula:
HOOC-Ar(OH)R9-Xy(ArR9OH)n (XVI)
where Ar is an aryl radical of 1 to 6 rings, R9 is an
alkyl group having from about 8 to 50 carbon atoms,
preferably 12 to 30 carbon atoms (optimatically about 12) ,
X is a sulfur (-S-) or methylene (-CH2-) bridge, y i5 a
number from 0 to 4 and n9 is a number from 0 to 4.
Preparation of the overbased methylene bridged
salicylatephenate salt is readily carried out by
conventional techniques such as by alkylation of a phenol
followed by phenation, carboxylation, hydrolysis, methylene
1 3 3 6 9 0 2
bridging via a coupling agent such as an alkylene dihalide
followed by salt formation concurrent with carbonation.
Overbased calcium salt of a methylene bridged
phenol-salicylic acids with a TBN of 60 to 150 is
representative of a rust-inhibitor highly useful in this
invention.
The sulfurized metal phenates can be considered
the "metal salt of a phenol sulfide" which thus refers to a
metal salt, whether neutral or basic, of a compound which
can be prepared by reacting an alkyl phenol sulfide with a
sufficient quantity of metal containing material to impart
the desired alkalinity to the sulfurized metal phenate.
Regardless of the manner in which they are
prepared, the sulfurized alkylphenols which are useful
contain from about 2 to about 14% by weight, preferably
about 4 to about 12 wt. % sulfur based on the weight of
sulfurized alkylphenol.
The sulfurized alkyl phenol is converted by
reaction with a metal containing material including oxides,
hydroxides and complexes in an amount sufficient to
neutralize said phenol and, if desired, to overbase the
product to a desired alkalinity by procedures well known in
the art. Preferred is a process of neutralization
utilizing a solution of metal in a glycol ether.
The neutral or normal sulfurized metal phenates
are tho~ in which the ratio of metal to phenol nucleus is
about 1:2. The "overbased" or "basic" sulfurized metal
phenate~ are sulfurized metal phenates wherein the ratio of
metal to phenol is greater than that of stoichiometry,
e.g., basic sulfurized metal dodecyl phenate has a metal
content up to and greater than 100% in excess of the metal
present in the corresponding normal sulfurized metal
phenates wherein the excess metal is produced in
oil-soluble or dispersible form (as by reaction with
co2) .
-46- 1 3369G2
According to a preferred embodiment the invention
there~orQ provides a crankcass lubricating composition-also
containing from 2 to 8000 parts per million of calcium or
magnesium.
The magnesium and/or calcium is generally present
as basic or neutral detergents such as the sulphonates and
phenates, our preferred additives are the neutral or basic
magnesium or calcium sulphonates. Preferably the oils
contain from 500 to 5000 parts per million of calcium or
magnesium. Basic magnesium and calcium sulfonates are
preferred.
These compositions of our invention may also
contain other additives such as those previously described,
and other metal containing additives, for example, those
containing barium and sodium.
The lubricating composition of the present
invention may also include copper lead bearing corrosion
inhibitors. Typically such compounds are the thiadiazole
polysulphides containing from 5 to 50 carbon atoms, their
derivatives and polymers thereof. Preferred materials are
the derivatives of 1,3,4 thiadiazoles such as those
described in U.S. Patents 2,719,125; 2,719,126; and
3,087,932; especially preferred is the compound 2,5-bis
(t-octadithio)-1,3,4 thiadiazole commercially available as
Amoco*150. Other similar materials also suitable are
describ~d in U.S. Patents 3,821,236; 3,904,537; 4,097,387;
4,107,059; 4,136,043; 4,188,299; and 4,193,882.
Other suitable additives are the thio and polythio
sulphenamide~ of thiadiazoles such as those described in
U.K. Patent Specification 1,560,830. When these compounds
are included in the lubricating composition, we prefer that
they be present in an amount from 0.01 to 10, preferably
0.1 to 5.0 weight percent based on the weight of the
composition.
Some of these numerous additives can provide a
multiplicity of effects, e.g. a dispersant-oxidation
*Trade mark
47 1 3 3 6 9 0 ~
inhibitor. This approach is well known and need not be
furthor elaborated herein.
Compositions containing these conventional
additives are typically blended into the base oil in
amounts effective to provide their normal attendant
function. Representative effective amounts of such
additives (as the respective active ingredients) in the
fully formulated oil are illustrated as follows:
Preferred Broad
Com~ositions Wt.% A.I. Wt.% A.I.
Ashless Dispersant (Component A) .01-8 .1-20
Friction Modifier (Component B) .01-1.5 .01-5
Copper Antioxidant (Component C) 10-200 ppm 5-500 ppm
by wt Cu by wt Cu
Viscosity Modifier .01-4 .01-12
Metal Detergents .01-3 .01-20
Corrosion Inhibitor .01-1.5 .01-5
Oxidation Inhibitor .01-1.5 .01-5
Pour Point Depressant .01-1.5 .01-5
Anti-Foaming Agents .001-0.15 .001-3
Anti-Wear Agents .001-1.5 .001-5
Mineral Oil Base Balance Balance
When other additives are employed, it may be
desirable, although not necessary, to prepare additive
concentrates comprising concentrated solutions or
dispersions of one or more of the dispersant, friction
modifier compound and copper antioxidant used in the
mixtures of this invention (in concentrate amounts
hereinabove described), together with one or more of said
other additives (said concentrate when constituting an
additive mixture being referred to herein as an
additive-package) whereby several additives can be added
simultaneously to the base oil to form the lubricating oil
composition. Dissolution of the additive concentrate into
the lubricating oil may be facilitated by solvents and by
mixing accompanied with mild heating, but this is not
essential. The concentrate or additive-package will
typically be formulated to contain the additives in proper
-48- 1 3 3 6 9 ~ 2
amounts to provide the desired concentration in the final
formulation when the additive-package is combined with a
predetermined amount of base lubricant. Thus, the additive
mixture of the present invention can be added to small
amounts of base oil or other compatible solvents along with
other desirable additives to form additive-packages
containing active ingredients in collective amounts of
typically from about 2.5 to about 90%, and preferably from
about 15 to about 75~, and most preferably from about 25 to
about 60% by weight additives in the appropriate
proportions with the remainder being base oil.
The final formulations may employ typically about
7 wt. % of the additive-package with the remainder being
base oil.
All of said weight percent~ expressed herein are
based on active ingredient (A.I.) content of the additive,
and/or upon the total weight of any additive-package, or
formulation which will be the sum of the A.I. weight of
each additive plus the weight of total oil or diluent.
This invention will be further understood by
reference to the following examples, wherein all parts and
percentages are by weight, unless otherwise noted and which
include preferred embodiments of the invention.
-49- 1 3 3 6 9 0 2
F~X'A~Pr.~ 1
Part A
A polyisobutenyl succinic anhydride (PIBSA) having
a SA:PIB ratio of 1.1 succinic anhydride (SA) moieties per
polyisobutylene (PIB) molecule (the PIB moieties having a
~n of about 2200 was aminated by reaction in S150N
mineral oil with a commercial grade of polyethyleneamine
(herein referred to as PAM) which was a mixture of
polyethyleneamines averaging about 5 to 7 nitrogens per
molecule, to form a polyisobutenyl succinimide containing
about 0.97 wt. % nitrogen.
Part B - Boration
A portion of the dispersant of Part A was reacted
with boric acid, then cooled and filtered to give a S150N
solution containing (50% a.i.) to provide borated
polyisobutenyl succinimide having a nitrogen content of
about 0.97 wt. %, a boron content of about 0.25 wt. %, and
50 wt. % of unreacted PIB and mineral oil (S150N).
The following lubricating oil additive package
concentrates were prepared using friction modifier
additives comprising the diethylene glycol ester of
linoleic dimer acid and selected dispersants from Examples
lA and lB, together with alkali metal overbased sulfonate
detergent inhibitor, copper salts of polyisobutylene
succinic anhydride (derived from polyisobutylene,
~n ' 900) antioxidant, zinc dialkyl dithio-
phosphate anti-wear agent (ZDDP), nonyl phenol sulfide
(NPS) supplemental antioxidant and SlOON diluent (where
indicated). The weight ratio of dispersant to each of the
other components was held constant within each of the two
sets of concentrates (that is the same ratio was used in
Concentrates A and ~, and the same ratio used for
Concentrates C and D).
Portions of each concentrate were stored at the
selected temperatures for prolonged periods to evaluate
their storage stability characteristics. The data thereby
obtained are summarized in Table I.
-50- 1 3 3 6 9 ~ 2
t` ~
~o~ o
A
O ~ ~r
a~ o O ~ D
H
CO CD
~ r~
O O
:~ ln ~ ~ ~
Z ~ Z
-
_
~ O 0 0 0
C~
~ ~æ~
.,
-51- l 3 3 6 9 0 2
From the foregoing tests, it can be seen that the
use of a non-borated dispersant in combination with a
copper antioxidant and the friction modifier additive
(Concentrates B and D) provided greatly improved storage
stability as compared to the use of a borated dispersant in
combination with the same antioxidant and friction modifier
additives (Formulations A and C).
The principles, preferred embodiments, and modes
of operation of the present invention have been described
in the foregoing specification. The invention which is
intended to be protected herein, however, is not to be
construed as limited to the particular forms disclosed,
since these are to ~e regarded a~ illustrativ~ rather than
restrictive. Variations and changes may be made by those
skilled in the art without departing from the spirit of the
invention.
