Note: Descriptions are shown in the official language in which they were submitted.
CA 02920022 2016-01-29
WO 2015/021135
PCT/US2014/049917
TITLE
Reduced Engine Deposits from Dispersant Treated with Copper
FIELD OF INVENTION
[0001] The invention provides a lubricating composition containing a
dispersant treated with copper to reduce the formation of high temperature
insoluble
solids formed during exposure of the composition to heat. The invention
further
relates to the use of the lubricating composition in an internal combustion
engine.
The invention further relates to a method of reducing insoluble deposits in an
engine using said dispersant treated with copper and said lubricating
composition.
BACKGROUND OF THE INVENTION
[0002] It is known that lubricants become less effective during their use
due
to exposure to the operating conditions of the device they are used in,
including
exposure to heat, oxygen, and partial combustion by-products generated by the
operation of the device. For example, engine oil becomes less effective during
its
use, in part due to exposure of the oil to acidic and pro-oxidant by-products.
These oxidized and acidic hydrocarbons of the lubricant can then go on to
cause
corrosion, wear and deposit problems.
[0003] Modern engine designs tend to incorporate smaller sump volumes
coupled with higher operating temperatures than ever before. These design
specifications lead to greater oxidative stress on the lubricant and increased
propensity to form high temperature deposits on key engine zones such as the
piston ring zone.
[0004] Given the continual demands placed on the lubricant by the modern
engine designs mentioned above, modern engine testing is necessarily becoming
more severe. For instance, the industry standard high temperature deposit test
(Sequence IIIG) is a very severe piston cleanliness test with high sump
temperatures and high load. There are a variety of bench tests that seek to
simulate
the deposit forming tendencies of lubricating oils in this and other engine
tests
including the Komatsu hot tube test (KHT). The procedure calls for circulating
an
oil through a hot glass tube (such as 232-320 C and more typically 270-290 C)
for a
1
CA 02920022 2016-01-29
WO 2015/021135
PCT/US2014/049917
specified period of time. At the end of test, the tube is rated visually for
deposits
with a rating of 10 being a perfectly clear tube and 0 being a black tube. The
test
gauges the innate tendency of the lubricant to form deposits in the absence of
combustion processes.
[0005] Current and proposed specifications for crankcase lubricants, such
as
GF-5 for passenger car motor oils, and PC-10 for heavy duty diesel engines
specify
increasingly stringent standards or limits to meet government specifications.
Of
particular concern are sulfur and phosphorus limits. Sulfur and phosphorus
from
the lubricant can end up in the catalytic converter. It is widely believed
that
lowering these limits in lubricants may have a serious impact on engine
performance, engine wear, and oxidation of engine oils. This is because
historically
a major contributor to phosphorus content in engine oils has been zinc
dialkyldithiophosphate (ZDP), and ZDP has long been used to impart antiwear
and
antioxidancy performance to engine oils. Thus, as reduced amounts of ZDP are
anticipated in engine oils, there is a need for alternatives to impart
protection
against deterioration in one or more of the properties of engine performance,
engine
wear, and oxidation of engine oils. Such improved protection is desirable
whether
or not ZDP and related materials are included in the lubricant. Desirable
lubricants
may be low in one or more of phosphorus and sulfur
[0006] There is a need for dual function additives that provide engine
deposit
control at high operating temperatures along with one of the conventional
functions
of an engine oil additive (such as dispersing of soot). In addition, it is
desirable if
this dual function additive also can function with low levels of conventional
antioxidants and/or low levels of metal or sulfur containing additives in the
lubricant.
SUMMARY OF THE INVENTION
[0007] The present invention relates to copper modified dispersants.
These
copper modified dispersant tend to minimize deposits formed as a result of oil
insoluble oxidation products on the walls of glass tubes and engine
components.
These copper modified dispersants also increase the oxidation induction times
of
the formulated lubricant in tests like the SAE CECL85.
2
CA 02920022 2016-01-29
WO 2015/021135
PCT/US2014/049917
[0008] It has now been discovered that the presence of copper, supplied
for
instance in the form of a reaction product of aminic (also known as ashless)
dispersants and copper compounds, such as Cu'l or Cu'2, provides a beneficial
effect on one or more of the above properties. In particular, such materials
as
copper PIB-succinimide dispersants impart a beneficial effect in one or more
of the
Komatsu Hot Tube deposits screen test (KHT).
[0009] The desired metal can be supplied as a Cu-modified dispersant,
such
as a succinimide dispersant, Mannich base, or hydrocarbyl based polymer
dispersants. Such materials may be prepared by forming a copper mixed
anhydride
between a copper sulfate or copper acetate and a hydrocarbyl-substituted
succinic
anhydride, such as an alkenyl- or alkyl- succinic anhydride. The resulting
copper-
succinate intermediate may be used directly or it may be reacted with any of a
number of materials, such as (a) a polyamine-based succinimide/amide
dispersant
having free, condensable ¨NH functionality; (b) the components of a polyamine-
based succinimide/amide dispersant, i.e., an alkenyl- or alkyl-succinic
anhydride
and a polyamine, (c) a hydroxy-containing polyester dispersant prepared by the
reaction of a substituted succinic anhydride with a polyol, aminoalcohol,
polyamine, or mixtures thereof. Alternatively, the copper-succinate
intermediate
may be reacted with other agents such as alcohols, aminoalcohols, ether
alcohols,
polyether alcohols or polyols, or fatty acids, and the product thereof either
used
directly to impart copper to a lubricant, or else further reacted with the
succinic
dispersants as described above. As an example of a dispersant post-treated
with
metal, 1 part (by mole) of copper sulfate, copper acetate, and/or copper
hydroxide
may be reacted with 2 parts (by mole) of a polyisobutene-substituted succinic
anhydride at 110 - 155 C or in one embodiment 140-150 C, for 5 to 6 hours to
provide a copper modified dispersant or intermediate. The resulting material
(30 g)
may be further reacted with a succinimide dispersant from polyisobutene-
substituted succinic anhydride and a polyethylenepolyamine mixture (127 g +
diluent oil) at 155 C for 1.5 hours, to produce a copper-modified succinimide
dispersant.
[0010] Dispersants are well known in the field of lubricants and include
primarily what is known as ashless-type dispersants and polymeric dispersants.
3
CA 02920022 2016-01-29
WO 2015/021135
PCT/US2014/049917
Ashless type dispersants are characterized by a polar group attached to a
relatively
high molecular weight hydrocarbon chain. Typical ashless dispersants include
nitrogen-containing dispersants such as N-substituted long chain alkenyl
succinimides, having a variety of chemical structures including typically
0 0
RiNq R1
H
N [ R2 N ] R2 pr
x
[0011] where each R1 is independently an alkyl group, frequently a
polyisobutyl group with a molecular weight of 500-5000, and R2 are alkylene
groups, commonly ethylene (C2H4) groups. Such molecules are commonly derived
from reaction of an alkenyl acylating agent with a polyamine, and a wide
variety of
linkages between the two moieties is possible in addition to the
representative imide
structure shown above, including a variety of amides and quaternary ammonium
salts. Succinimide dispersants are more fully described in U.S. Patents
4,234,435
and 3,172,892.
[0012] The invention further provides a method of lubricating an internal
combustion engine comprising the step of: supplying to the internal combustion
engine
the lubricating composition described herein.
DETAILED DESCRIPTION OF THE INVENTION
[0013] Various preferred features and embodiments will be described below
by way of non-limiting illustration.
[0014] The amounts of additives present in the lubricating composition
disclosed herein are quoted on an oil free basis, i.e., amount of actives,
unless
otherwise noted.
Oils of Lubricating Viscosity
[0015] The lubricating compositions of the invention comprise an oil of
lubricating viscosity. Suitable oils include both natural and synthetic oils,
oil
derived from hydrocracking, hydrogenation, and hydro finishing, unrefined,
refined,
re-refined oils or mixtures thereof.
4
CA 02920022 2016-01-29
WO 2015/021135
PCT/US2014/049917
[0016] Unrefined oils are those obtained directly from a natural or
synthetic
source generally without (or with little) further purification treatment.
[0017] 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.
Purification techniques are known in the art and include solvent extraction,
secondary distillation, acid or base extraction, filtration, percolation and
the like.
[0018] Re-refined oils are also known as reclaimed or reprocessed oils,
and
are obtained by processes similar to those used to obtain refined oils and
often are
additionally processed by techniques directed to removal of spent additives
and oil
breakdown products.
[0019] Natural oils useful in making the inventive lubricants include
animal
oils, vegetable oils (e.g., castor oil,), mineral lubricating oils such as
liquid
petroleum oils and solvent-treated or acid-treated mineral lubricating oils of
the
paraffinic, naphthenic or mixed paraffinic-naphthenic types and oils derived
from
coal or shale or mixtures thereof.
[0020] Synthetic lubricating oils are useful and include hydrocarbon oils
such as polymerized, oligomerised, or interpolymerised olefins (e.g.,
polybutylenes,
polypropylenes, propyleneisobutylene copolymers); poly(1-hexenes), poly(1-
octenes), trimers or oligomers of 1-decene, e.g., poly(1-decenes), such
materials
being often referred to as poly a-olefins, and mixtures thereof; alkyl-
benzenes (e.g.,
dodecylbenzenes, tetra-decylbenzenes, dinonylbenzenes, di-(2-ethylhexyl)-
benzenes); polyphenyls (e.g., biphenyls, terphenyls, alkylated polyphenyls);
diphenyl alkanes, alkylated diphenyl alkanes, alkylated diphenyl ethers and
alkylated diphenyl sulphides and the derivatives, analogs and homologs thereof
or
mixtures thereof.
[0021] Other synthetic lubricating oils include polyol esters (such as
Priolube03970), diesters, liquid esters of phosphorus-containing acids (e.g.,
tricresyl phosphate, trioctyl phosphate, and the diethyl ester of decane
phosphonic
acid), or polymeric tetrahydrofurans. Synthetic oils may be produced by
Fischer-
Tropsch reactions and typically may be hydroisomerised Fischer-Tropsch
hydrocarbons or waxes. In one embodiment, oils may be prepared by a Fischer-
Tropsch gas-to-liquid synthetic procedure as well as other gas-to-liquid oils.
CA 02920022 2016-01-29
WO 2015/021135
PCT/US2014/049917
[0022] Oils of lubricating viscosity may also be defined as specified in
April
2008 version of "Appendix E - API Base Oil Interchangeability Guidelines for
Passenger Car Motor Oils and Diesel Engine Oils", section 1.3 Sub-heading 1.3.
"Base Stock Categories". In one embodiment, the oil of lubricating viscosity
may
be an API Group II or Group III oil. In one embodiment, the oil of lubricating
viscosity may be an API Group I oil.
[0023] The amount of the oil of lubricating viscosity present is
typically the
balance remaining after subtracting from 100 wt. % the sum of the amount of
the
compound of the invention and the other performance additives.
[0024] The lubricating composition may be in the form of a concentrate
and/or a fully formulated lubricant. If the lubricating composition of the
invention
(comprising the additives disclosed herein) is in the form of a concentrate
which
may be combined with additional oil to form, in whole or in part, a finished
lubricant), the ratio of the of these additives to the oil of lubricating
viscosity
and/or to diluent oil include the ranges of 1:99 to 99:1 by weight, or 80:20
to 10:90
by weight.
The Dispersant Treated with Copper
[0025] The present invention provides a lubricating composition
containing
an oil of lubricating viscosity and an additive comprising a dispersant
treated with
copper.
[0026] In one embodiments, the ashless dispersant reacted with copper,
hereinafter additive, may be present in a lubricating composition in a
concentration
from about 0.5 to about 10 weight percent, more desirably from about 1 to
about 5
weight percent, and preferably from about 1.5 to about 3.5 weight percent
based on
the total weight of the lubricating compositions. Desirably, the amount of
copper
incorporated into the lubricant from treating the dispersant in the
lubricating
composition is from about 5, 6, or 7 to about 500 parts per million parts by
weight
(ppm) of lubricating composition, more desirably from about 5, 6, 8, or 10 to
about
50, 100, or 350 ppm, and in one embodiment, from about 40 or 50 to 150 or 200
PPm=
6
CA 02920022 2016-01-29
WO 2015/021135
PCT/US2014/049917
[0027] Generally, the ashless dispersant and the copper compound will be
reacted together at temperatures of at least 100 C, more desirably at least
140 C for
times such as desirably at least 1 hour and more desirably at least 2 or 4
hours so as
to form a reaction product where a significant portion of copper is physically
or
chemically associated with the dispersant. While a reaction product is the
desired
result, it is acknowledge that some copper and some ashless dispersant may
remain
in the form of reactants that haven't been converted to associated materials.
[0028] Suitable dispersants for use in the compositions of the present
invention include succinimide dispersants. In one embodiment, the dispersant
may
be present as a single dispersant. In one embodiment, the dispersant may be
present
as a mixture of two or three different dispersants, wherein at least one may
be a
succinimide dispersant.
[0029] The succinimide dispersant may be a derivative of an aliphatic
polyamine, or mixtures thereof. The aliphatic polyamine may be aliphatic
polyamine
such as an ethylenepolyamine, a propylenepolyamine, a butylenepolyamine, or
mixtures thereof. In one embodiment, the aliphatic polyamine may be
ethylenepolyamine. In one embodiment, the aliphatic polyamine may be selected
from the group consisting of ethylenediamine, diethylenetriamine,
triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, polyamine
still bottoms, and mixtures thereof.
[0030] The dispersant may be a N-substituted long chain alkenyl
succinimide. Examples of N-substituted long chain alkenyl succinimide include
polyisobutylene succinimide. Typically, the polyisobutylene from which
polyisobutylene succinic anhydride is derived has a number average molecular
weight of 350 to 5000, or 550 to 3000 or 750 to 2500. Succinimide dispersants
and
their preparation are disclosed, for instance in US Patents 3,172,892;
3,219,666;
3,316,177; 3,340,281; 3,351,552; 3,381,022; 3,433,744; 3,444,170; 3,467,668;
3,501,405; 3,542,680; 3,576,743; 3,632,511; 4,234,435; Re 26,433; 6,165,235;
7,238,650; and EP Patent Application 0 355 895 A.
[0031] Another class of ashless dispersant is Mannich base type. These
are
materials which are formed by the condensation of a higher molecular weight,
alkyl
7
CA 02920022 2016-01-29
WO 2015/021135
PCT/US2014/049917
substituted phenol, an alkylene polyamine, and an aldehyde such as
formaldehyde.
Such materials may have the general structure
OH OH
--1 CH2-NH-(R2NH)x-R2NHCH2
I
-V
X
R1 R1
(including a variety of isomers and the like) and are described in more detail
in U.S.
Patent 3,634,515.
[0032] Another class of ashless dispersant is high molecular weight ester
type. These materials are similar to the above-described succinimides except
that
they may be seen as having been prepared by reaction of a hydrocarbyl
acylating
agent and a polyhydric aliphatic alcohol such as glycerol, pentaerythritol, or
sorbitol. Such materials are described in more detail in U.S. Patent 3,381,022
and
3,306,908.
[0033] Other dispersants include polymeric dispersant additives, which
are
generally hydrocarbon-based polymers which contain polar functionality to
impart
dispersancy characteristics to the polymer.
[0034] Dispersants can also be post-treated by reaction with any of a
variety
of agents. Among these are urea, thiourea, dimercaptothiadiazoles, carbon
disulfide, aldehydes, ketones, carboxylic acids, hydrocarbon-substituted
succinic
anhydrides, nitriles, epoxides, boron compounds, and phosphorus compounds.
References detailing such treatment are listed in U.S. Patent 4,654,403 and
3,305,905.
Additional Performance Additives
[0035] The compositions of the invention may optionally comprise one or
more additional performance additives. These additional performance additives
may include one or more metal deactivators, viscosity modifiers, detergents,
friction modifiers, antiwear agents, corrosion inhibitors, dispersants (other
than the
compound of the present invention), dispersant viscosity modifiers, extreme
pressure agents, antioxidants, foam inhibitors, demulsifiers, pour point
depressants,
seal swelling agents, and any combination or mixture thereof. Typically, fully-
8
CA 02920022 2016-01-29
WO 2015/021135
PCT/US2014/049917
formulated lubricating oil will contain one or more of these performance
additives,
and often a package of multiple performance additives.
[0036] In one embodiment, the invention provides a lubricating
composition
further comprising an antiwear agent, a dispersant viscosity modifier, a
friction
modifier, a viscosity modifier, an antioxidant, an overbased detergent, or a
combination thereof, where each of the additives listed may be a mixture of
two or
more of that type of additive. In one embodiment, the invention provides a
lubricating
composition further comprising an antiwear agent, a dispersant viscosity
modifier, a
friction modifier, a viscosity modifier (typically an olefin copolymer such as
an
ethylene-propylene copolymer), an antioxidant (including phenolic and/or
aminic
antioxidants), an overbased detergent (including overbased sulfonates and
phenates), or a combination thereof, where each of the additives listed may be
a
mixture of two or more of that type of additive.
[0037] In one embodiment, the lubricating composition of the invention
further
includes an antiwear agent such as a phosphorus-containing antiwear agent such
as a
dithiophosphate agent such as a metal dihydrocarbyl dithiophosphate (typically
zinc
dialkyldithiophosphate (ZDDP)), wherein the metal dihydrocarbyl
dithiophosphate
contributes at least 100 ppm, at least 200 ppm, or at least 250 ppm, or 200
ppm to
1000 ppm, or 250 or 300 ppm to 800 ppm, or 300 or 400 ppm to 600 ppm of
phosphorus to the lubricating composition. In one embodiment, the lubricating
composition is free of or substantially free (meaning less than 100, less than
50 or
less than 20 ppm of phosphorus from a metal dialkyldithiophosphate such as
zinc
dialkyldithiophosphate).
[0038] In one embodiment, the lubricating composition of the invention
further comprises a dispersant viscosity modifier. The dispersant viscosity
modifier
may be present at 0 wt. % to 5 wt. %, or 0 wt. % to 4 wt. %, or 0.05 wt. % to
2 wt.
% of the lubricating composition.
[0039] Suitable dispersant viscosity modifiers include functionalized
polyolefins, for example, ethylene-propylene copolymers that have been
functionalized with an acylating agent such as maleic anhydride and an amine;
polymethacrylates functionalized with an amine, or esterified styrene-maleic
anhydride copolymers reacted with an amine. More detailed description of
9
CA 02920022 2016-01-29
WO 2015/021135
PCT/US2014/049917
dispersant viscosity modifiers are disclosed in International Publication
W02006/015130 or U.S. Patents 4,863,623; 6,107,257; 6,107,258; and 6,117,825.
In one embodiment, the dispersant viscosity modifier may include those
described
in U.S. Patent 4,863,623 (see column 2, line 15 to column 3, line 52) or in
International Publication W02006/015130 (see page 2, paragraph [0008] and
preparative examples are described paragraphs [0065] to [0073]).
[0040] In one embodiment it is desirable if the lubricant composition has
low
level or is free of metals selected from the group of molybdenum, titanium,
and
boron. In one embodiment the lubricant composition has less than 100, less
than
50, less than 20, less than 20 or 0 ppm of molybdenum based on the weight of
the
lubricant composition. Ppm is an abbreviation for parts by weight per million
parts
by weight of the total composition. In one embodiment the lubricant
composition
has less than 50, less than 30, less than 10, less than 5 or 0 ppm of titanium
based
on the weight of the lubricant composition. In one embodiment the lubricant
composition has less than 100, less than 80, less than 50, less than 25, less
than 10,
or 0 ppm of boron based on the weight of the lubricant composition. In one
embodiment the limitations on molybdenum, titanium, and boron are all together
applied to the composition.
[0041] In one embodiment, the invention provides a lubricating
composition
further comprising an overbased detergent. The overbased detergent may be
selected from the group consisting of sulfur-free phenates, sulfur-containing
phenates, sulfonates, salixarates, salicylates, and mixtures thereof.
[0042] The overbased detergent may also include "hybrid" detergents
formed
with mixed surfactant systems including phenate and/or sulfonate components,
e.g.
phenate/salicylates, sulfonate/phenates, sulfonate/salicylates,
sulfonates/phenates/salicylates, as described for example, in US Patents
6,429,178;
6,429,179; 6,153,565; and 6,281,179. Where, for example, a hybrid
sulfonate/phenate detergent is employed, the hybrid detergent would be
considered
equivalent to amounts of distinct phenate and sulfonate detergents introducing
like
amounts of phenate and sulfonate soaps, respectively.
[0043] Typically, an overbased detergent may be sodium salts, calcium
salts,
magnesium salts, or mixtures thereof of the phenates, sulfur containing
phenates,
CA 02920022 2016-01-29
WO 2015/021135
PCT/US2014/049917
sulfonates, salixarates and salicylates. Overbased phenates and salicylates
typically
have a total base number of 180 to 450 TBN. Overbased sulfonates typically
have a
total base number of 250 to 600, or 300 to 500. Overbased detergents are known
in
the art. In one embodiment, the sulfonate detergent may be predominantly a
linear
alkylbenzene sulfonate detergent having a metal ratio of at least 8 as is
described in
paragraphs [0026] to [0037] of US Patent Publication 2005065045 (and granted
as US
7,407,919). The linear alkylbenzene sulfonate detergent may be particularly
useful for
assisting in improving fuel economy. The linear alkyl group may be attached to
the
benzene ring anywhere along the linear chain of the alkyl group, but often in
the 2-, 3- or
4- position of the linear chain. In some instances, the linear alkyl group may
be attached
in predominantly the 2- position, resulting in the linear alkylbenzene
sulfonate detergent.
The overbased detergent may be present at 0 wt. % to 15 wt. %, 0.1 wt. % to 10
wt.
%, 0.2 wt. % to 8 wt. %, or 0.2 wt. % to 3 wt. %. For example, in a heavy duty
diesel engine the detergent may be present at or 2 wt. % to 3 wt. % of the
lubricating composition. For a passenger car engine the detergent may be
present at
0.2 wt. % to 1 wt. % of the lubricating composition.
[0044] In one embodiment, the lubricating composition includes an
antioxidant, or mixtures thereof. The antioxidant may be present at 0 wt. % to
15
wt. %, 0.1 wt. % to 10 wt. %, or 0.5 wt. % to 5 wt. % of the lubricating
composition.
[0045] Antioxidants include sulfurized olefins, alkylated diarylamines
(typically alkylated phenyl naphthyl amines, for example those commercially
available as Irganox0 L 06 from CIBA, or alkylated diphenylamines such as
dinonyl diphenylamine, octyl diphenylamine, dioctyl diphenylamine), hindered
phenols, molybdenum compounds (such as molybdenum dithiocarbamates), or
mixtures thereof.
[0046] The hindered phenol antioxidant often contains a secondary butyl
and/or a tertiary butyl group as a sterically hindering group. The phenol
group may
be further substituted with a hydrocarbyl group (typically linear or branched
alkyl)
and/or a bridging group linking to a second aromatic group. Examples of
suitable
hindered phenol antioxidants include 2,6-di-tert-butylphenol, 4-methy1-2,6-di-
tert-
butylphenol, 4-ethyl-2,6-di-tert-butylphenol, 4-propy1-2,6-di-tert-butylphenol
or 4-
11
CA 02920022 2016-01-29
WO 2015/021135
PCT/US2014/049917
butyl-2,6-di-tert-butylphenol, or 4-dodecy1-2,6-di-tert-butylphenol. In one
embodiment, the hindered phenol antioxidant may be an ester and may include
e.g.,
IrganoxTM L-135 from Ciba. A more detailed description of suitable ester-
containing hindered phenol antioxidant chemistry is found in US Patent
6,559,105.
[0047] Examples of friction modifiers include long chain fatty acid
derivatives of amines, fatty esters, or epoxides; fatty imidazolines such as
condensation products of carboxylic acids and polyalkylene-polyamines; amine
salts of alkylphosphoric acids; fatty alkyl tartrates; fatty alkyl
tartrimides; or fatty
alkyl tartramides. In some embodiments, the term fatty, as used herein, can
mean
having a C8-22 linear alkyl group.
[0048] Friction modifiers may also encompass materials such as sulfurised
fatty compounds and olefins, molybdenum dialkyldithiophosphates, molybdenum
dithiocarbamates, sunflower oil or monoester of a polyol and an aliphatic
carboxylic acid.
[0049] In one embodiment, the friction modifier may be selected from the
group consisting of long chain fatty acid derivatives of amines, long chain
fatty
esters, or long chain fatty epoxides; fatty imidazolines; amine salts of
alkylphosphoric acids; fatty alkyl tartrates; fatty alkyl tartrimides; and
fatty alkyl
tartramides. The friction modifier may be present at 0 wt. % to 6 wt. %, or
0.05 wt.
% to 4 wt. %, or 0.1 wt. % to 2 wt. % of the lubricating composition.
[0050] In one embodiment, the friction modifier may be a long chain fatty
acid ester. In another embodiment, the long chain fatty acid ester may be a
monoester or a diester or a mixture thereof, and in another embodiment, the
long
chain fatty acid ester may be a triglyceride.
[0051] Other performance additives such as corrosion inhibitors include
those described in paragraphs 5 to 8 of US Application U505/038319, published
as
W02006/047486, octyl octanamide, condensation products of dodecenyl succinic
acid or anhydride and a fatty acid such as oleic acid with a polyamine. In one
embodiment, the corrosion inhibitors include the Synalox0 corrosion inhibitor.
The Synalox0 corrosion inhibitor may be a homopolymer or copolymer of
propylene oxide. The Synalox0 corrosion inhibitor is described in more detail
in a
product brochure with Form No. 118-01453-0702 AMS, published by The Dow
12
CA 02920022 2016-01-29
WO 2015/021135
PCT/US2014/049917
Chemical Company. The product brochure is entitled "SYNALOX Lubricants,
High-Performance Polyglycols for Demanding Applications."
[0052] Metal deactivators including derivatives of benzotriazoles
(typically
tolyltriazole), dimercaptothiadiazole derivatives, 1,2,4-triazoles,
benzimidazoles, 2-
alkyldithiobenzimidazoles, or 2-alkyldithiobenzothiazoles; foam inhibitors
including copolymers of ethyl acrylate and 2-ethylhexyl acrylate and
copolymers of
ethyl acrylate and 2-ethylhexylacrylate and vinyl acetate; demulsifiers
including
trialkyl phosphates, polyethylene glycols, polyethylene oxides, polypropylene
oxides and (ethylene oxide-propylene oxide) polymers; pour point depressants
including esters of maleic anhydride-styrene, polymethacrylates, polyacrylates
or
polyacrylamides may be useful.
[0053] Pour point depressants that may be useful in the compositions of
the
invention include poly(alphaolefins), esters of maleic anhydride-styrene,
poly(meth)acrylates, polyacrylates or polyacrylamides.
[0054] In different embodiments, the lubricating composition may have a
composition as described in the following Table 1:
Table 1
Additive Embodiments (wt. %)
A B C
Additive of Invention, dispersant 0. 5 to 10 1 to 6 1.5 to 3.5
treated with copper
Dispersant Viscosity Modifier 0 or 0.05 to 5 0 or 0.05 to 4
0.05 to 2
Overbased Detergent 0 or 0.05 to 15 0.1 to 10 0.2 to 8
Antioxidant aminic and/or 0 or 0.05 to 15 0.1 to 10 0.5 to 5
phenolic
Antiwear Agent, e.g. 0 or 0.05 to 15 0.1 to 10 0.3 to 5
dithiophosphate
Friction Modifier 0 or 0.05 to 6 0.05 to 4 0.1 to 2
Viscosity Modifier 0 or 0.05 to 10 0.5 to 8 1 to 6
Any Other Performance Additive 0 or 0.05 to 10 0 or 0.05 to 8 0
or 0.05 to 6
Oil of Lubricating Viscosity Balance to 100 Balance to 100
Balance to 100
13
CA 02920022 2016-01-29
WO 2015/021135
PCT/US2014/049917
[0055] The present invention provides a surprising ability to reduce high
temperature deposit formation on walls of the reactor in the KHT test simply
by
modifying the dispersant with a few hundred ppm of copper.
Industrial Application
[0056] In one embodiment, the invention provides a method of lubricating
an
internal combustion engine comprising the step of supplying to the internal
combustion
engine a lubricating composition as disclosed herein. Generally, the lubricant
is added to
the lubricating system of the internal combustion engine, which then delivers
the
lubricating composition to the critical parts of the engine that require
lubrication during
its operation.
[0057] The lubricating compositions described above may be utilized in an
internal combustion engine. The engine components may have a surface of steel
or
aluminum (typically a surface of steel), and may also be coated for example
with a
diamond like carbon (DLC) coating.
[0058] An aluminum surface may be comprised of an aluminum alloy that
may be a eutectic or hyper-eutectic aluminum alloy (such as those derived from
aluminum silicates, aluminum oxides, or other ceramic materials). The aluminum
surface may be present on a cylinder bore, cylinder block, or piston ring
having an
aluminum alloy, or aluminum composite.
[0059] The internal combustion engine may or may not have an Exhaust Gas
Recirculation (EGR) system. The internal combustion engine may be fitted with
an
emission control system or a turbocharger. Examples of the emission control
system
include diesel particulate filters (DPF), or systems employing selective
catalytic
reduction (SCR).
[0060] In one embodiment, the internal combustion engine may be a diesel
fuelled or biofuelled engine (typically a heavy duty diesel engine), a
gasoline
fuelled engine, a natural gas fuelled engine or a mixed gasoline/alcohol
fuelled
engine. In one embodiment, the internal combustion engine may be a diesel
fuelled
engine and in another embodiment, a gasoline fuelled engine.
[0061] The internal combustion engine may be a 2-stroke or 4-stroke
engine.
Suitable internal combustion engines include marine diesel engines, aviation
piston
engines, low-load diesel engines, and automobile and truck engines.
14
CA 02920022 2016-01-29
WO 2015/021135
PCT/US2014/049917
[0062] The internal combustion engine of the present invention is
distinct
from gas turbine. In an internal combustion engine, individual combustion
events
which through the rod and crankshaft translate from a linear reciprocating
force into a
rotational torque. In contrast, in a gas turbine (may also be referred to as a
jet engine) it
is a continuous combustion process that generates a rotational torque
continuously
without translation and can also develop thrust at the exhaust outlet. These
differences
result in the operation conditions of a gas turbine and internal combustion
engine
different operating environments and stresses.
[0063] The lubricant composition for an internal combustion engine may be
suitable for any engine lubricant irrespective of the sulfur, phosphorus or
sulfated
ash (ASTM D-874) content. The sulfur content of the engine oil lubricant may
be 1
wt. % or less, 0.8 wt. % or less, 0.5 wt. % or less, or 0.3 wt. % or less. In
one
embodiment, the sulfur content may be in the range of 0.001 wt. % to 0.5 wt.
%, or
0.01 wt. % to 0.3 wt. %. The phosphorus content may be 0.2 wt. % or less, 0.12
wt.
% or less, 0.1 wt. % or less, 0.085 wt. % or less, 0.08 wt. % or less, 0.06
wt. % or
less, 0.055 wt. % or less, or 0.05 wt. % or less. In one embodiment, the
phosphorus
content may be 100 ppm to 1000 ppm, or 200 ppm to 600 ppm. The total sulfated
ash content may be 2 wt. % or less, 1.5 wt. % or less, or 1.1 wt. % or less, 1
wt. %
or less, 0.8 wt. % or less, 0.5 wt. % or less, or 0.4 wt. % or less. In one
embodiment, the sulfated ash content may be 0.05 wt. % to 0.9 wt. %, 0.1 wt. %
to
0.2 wt. % or to 0.45 wt. %. Desirably in one embodiment, the amount of sulfur
from all the sulfur containing additives is from about 500 or 1000 to about
2500
ppm sulfur, based on the weight of the lubricant compositions, more desirably
from
about 500 to about 1500 ppm.
[0064] In one embodiment, the lubricating composition may be an engine
oil,
wherein the lubricating composition may be characterized as having at least
one of
(i) a sulfur content of 0.5 wt. % or less, (ii) a phosphorus content of 0.1
wt. % or
less, (iii) a sulfated ash content of 1.5 wt. % or less, or combinations
thereof.
EXAMPLES
[0065] The invention will be further illustrated by the following
examples,
which set forth particularly advantageous embodiments. While the examples are
provided to illustrate the invention, they are not intended to limit it.
CA 02920022 2016-01-29
WO 2015/021135
PCT/US2014/049917
Comparative Example 1 (CEX1): Synthesis of Succinimide Dispersant from
2000 Mn Conventional Polyisobutylene.
[0066] A 2 L 4-necked round bottom flask was equipped with a stirrer,
dropping funnel, sub-surface tube, thermowell, Dean-Stark trap and Friedrick's
condenser, charged with polyisobutylene succinic anhydride (550 g, 2000 Mn,
conventional PIBSA, TAN = 68), diluent oil (505 g) and purged with nitrogen.
Polyethylene amine still bottoms (25 g, 34 wt. % N) were added to the dropping
funnel. The mixture was warmed to 110 C with stirring. The polyamine was added
drop-wise to the sub-surface tube over 35 min. The temperature was increased
to
155 C and the preparation was stirred for 5.25 h. 2.2 g water was collected in
the
Dean-Stark trap. Diatomaceous earth (16 g) was added to the mixture and the
dispersant was filtered through a supplemental pad of diatomaceous earth (16
g) to
yield a succinimide dispersant as a clear brown oil (1013 g, KV100 = 548, %N =
0.79).
Comparative Example 2 (CEX2): Synthesis of Al-Containing Dispersant
[0067] The dispersant of Comparative Example 1(1400 g) was charged to a
2 L 4-necked round bottom flask equipped with a stirrer, thermowell, sub-
surface
tube, Dean-Stark trap and Friedrick's condenser and the flask was purged with
nitrogen. The dispersant was warmed to 90 C with stirring. Al(PrO)3 (45 g) was
charged in one aliquot and the temperature was increased to 155 C. The mixture
was stirred for 5 h, filtered through diatomaceous earth and cooled to yield a
brown
oil (1375 g, KV100 = 4626 cSt, 0.27% Al).
Comparative Example 3 (CEX3): Synthesis of La-Containing Dispersant
[0068] The procedure of Comparative Example 2 was used except the
dispersant of Comparative Example 1(1300 g) was treated with La(OH)3 (7.1 g)
to
yield a brown oil (1178 g, KV100 = 487 cSt).
16
CA 02920022 2016-01-29
WO 2015/021135
PCT/US2014/049917
Comparative Example 4 (CEX4): Synthesis of Ba-Containing Dispersant
[0069] The procedure of Comparative Example 2 was used except the
dispersant of Comparative Example 1(1300 g) was treated with Ba(OH)208H20 (12
g) to yield a brown oil (1187 g, KV100 = 478 cSt, 0.38% Ba).
Comparative Example 5 (CEX5): Synthesis of Zn-Containing Dispersant
[0070] The procedure of Comparative Example 2 was used except the
dispersant of Comparative Example 1(1300 g) was treated with Zn(0Ac)2 (18 g)
to
yield a brown oil (1216 g, KV100 = 682 cSt, 0.39% Zn).
Example 6 (EX6): Synthesis of Cu-Containing Dispersant 1
[0071] The procedure of Comparative Example 2 was used except the
dispersant of Comparative Example 1(1300 g) was treated with CuSO4 (13 g) to
yield a light purple oil (1216 g, KV100 = 544 cSt, 0.08% Cu).
Example 7 (EX7): Synthesis of Cu-Containing Dispersant 2
[0072] The procedure of Comparative Example 2 was used except the
dispersant of Comparative Example 1 (1300 g) was treated with Cu(OAc)201-120
(17
g) to yield a green oil (1200 g, KV100 = 611 cSt, 0.39% Cu).
Example 8 (EX8): Dilution of Example 7 with Comparative Example 1 (50:50)
[0073] The Dipsersant 2 was mixed 50:50 by weight with Comparative
Example 1 to see the effect of concentration of the metal treated dispersant.
Example 9 (EX9): Dilution of Example 7 with Comparative Example 1 (25:75)
[0074] The Dipsersant 2 was mixed 50:50 by weight with Comparative
Example 1 to see the effect of concentration of the metal treated dispersant.
Preparative Example 10 (PEX10): Synthesis of High TBN Succinimide
Dispersant from 2000 Mn Conventional Polyisobutylene.
[0075] A 2 L 4-necked round bottom flask was equipped with a stirrer,
dropping funnel, sub-surface tube, thermowell, Dean-Stark trap and Friedrick's
17
CA 02920022 2016-01-29
WO 2015/021135
PCT/US2014/049917
condenser, charged with polyisobutylene succinic anhydride (600 g, 2000 Mn,
conventional PIBSA, TAN = 73), diluent oil (635 g) and purged with nitrogen.
Polyethylene amine still bottoms (43 g, 34 wt. % N) were added to the dropping
funnel. The mixture was warmed to 110 C with stirring. The polyamine was added
drop-wise to the sub-surface tube over 35 min. The temperature was increased
to
155 C and the preparation was stirred for 5.25 h. 3.1 g water was collected in
the
Dean-Stark trap. Diatomaceous earth (18 g) was added to the mixture and the
dispersant was filtered through a supplemental pad of diatomaceous earth (18
g) to
yield a succinimide dispersant as a clear brown oil (1117 g, KV100 = 183, %N =
1.2).
Example 11 (EX11): Synthesis of Cu-Containing Dispersant from
Cu(OAc)2xH20
[0076] The procedure of Comparative Example 2 was used except the
dispersant of Comparative Example 10 (1300 g) was treated with Cu(OAc)2xH20
(16.6 g) to yield a brown oil (1200.0 g, KV100 = 611 cSt).
Lubricating Oils:
[0077] The materials from Examples CEX1- EX11 were blended into an API
SN capable lubricating oil (5W-30) in group II basestocks as detailed in Table
2.
Component descriptions and treat rates are listed on a diluent oil free basis.
Comparative Lubricant 1 contains Comparative Dispersant Example 1 which is a
baseline that contains no succinimide dispersant post-treatment with a metal.
Comparative Lubricants 2-5 (CL2-CL5) contain equivalent treat rates of
Comparative Dispersant Examples 2-5 containing Al, La, Ba and Zn post-
treatments, respectively. These metals have only one stable oxidation state.
Lubricants 6-9 and 11 (L6-L9 and L11) have different types or amounts of
copper
as a post treatment for the dispersant used in each example.
18
CA 02920022 2016-01-29
WO 2015/021135 PCT/US2014/049917
Table 2. Formulas Tested (Treat Rates on Oil Free Basis).
Lubricant # CL1 CL2 CL3 CL4 CL5 L6 L7
L8 L9 L11
Dispersant CEX1
CEX2 CEX3 CEX4 CEX5 EX6 EX7 EX8 EX9 EX11
Disp. Treat 2.12 2.12 2.12 2.12 2.12 2.12 2.12 2.12
2.12 2.12
Group II Oil BALANCE to 100 g
Ca Sulfonatel 0.74g
Na Sulfonate2 0.17
A03 2.16
ZDP4 0.79
VI Improvers 0.7
Other6 0.2
Disp Metal - Al La Ba Zn Cu Cu Cu Cu Cu
%M (PP m) 0 160 150 150 155 33 33 17 8
33
1 Combination of 520 TBN and 690 TBN overbased calcium sulfonate detergents
2 Overbased sodium sulfonate detergent (650 TBN)
3 C3/C6 secondary zinc dialkyldithiophosphate (ZDDP)
4 Combination of hindered phenol, alkylated diphenyl amine, and sulfurized
olefin
Ethylene-propylene copolymer
6 Other additives include friction modifier(s), foam inhibitor(s), and/or pour
point depressant(s)
Performance Testing:
[0078] The Lubricants from Table 1 were tested in the KHT test. Briefly,
5
mL of the test oil was pumped through a heated glass capillary tube at 0.31
cc/h.
The sample was purged with air at a rate of 10 cc/min. The sample was
circulated
through the glass tube for 16 h while the tube is heated to 280 C. At the end
of
test, the tube is visually rated according to the scale found in Figure 1 (10
= clean
tube, 0 = dirty tube).
[0079] Table 3 shows the KHT performance of the Lubricants from Table 2.
The comparative lubricants (CL1-CL5) all gave dirty black tubes (0) while the
inventive lubricants (L6-L8) all gave much cleaner tubes in the range of 8.5-
9.
19
CA 02920022 2016-01-29
WO 2015/021135
PCT/US2014/049917
Table 3. KHT Performance of the Lubricants from Table 1.
Lubricant CL! CL2
CL3 CL4 CL5 L6 L7 L8
KHT Rating 0 0 0 0 0 8.5 9 8.5
[0080] It is known that some of the materials described above may
interact in
the final formulation, so that the components of the final formulation may be
different from those that are initially added. The products formed thereby,
including the products formed upon employing lubricant composition of the
present
invention in its intended use, may not be susceptible of easy description.
Nevertheless, all such modifications and reaction products are included within
the
scope of the present invention; the present invention encompasses lubricant
composition prepared by admixing the components described above.
[0081] Each of the documents referred to above is incorporated herein by
reference, as is the priority document and all related applications, if any,
which this
application claims the benefit of. Except in the Examples, or where otherwise
explicitly indicated, all numerical quantities in this description specifying
amounts
of materials, reaction conditions, molecular weights, number of carbon atoms,
and
the like, are to be understood as modified by the word "about." Unless
otherwise
indicated, each chemical or composition referred to herein should be
interpreted as
being a commercial grade material which may contain the isomers, by-products,
derivatives, and other such materials which are normally understood to be
present
in the commercial grade. However, the amount of each chemical component is
presented exclusive of any solvent or diluent oil, which may be customarily
present
in the commercial material, unless otherwise indicated. It is to be understood
that
the upper and lower amount, range, and ratio limits set forth herein may be
independently combined. Similarly, the ranges and amounts for each element of
the
invention may be used together with ranges or amounts for any of the other
elements.
[0082] As used herein, the term "hydrocarbyl substituent" or "hydrocarbyl
group" is used in its ordinary sense, which is well-known to those skilled in
the art.
Specifically, it refers to a group having a carbon atom directly attached to
the
CA 02920022 2016-01-29
WO 2015/021135
PCT/US2014/049917
remainder of the molecule and having predominantly hydrocarbon character.
Examples of hydrocarbyl groups include:
(i) hydrocarbon substituents, that is, aliphatic (e.g., alkyl or alkenyl),
alicyclic
(e.g., cycloalkyl, cycloalkenyl) substituents, and aromatic-, aliphatic-, and
alicyclic-
substituted aromatic substituents, as well as cyclic substituents wherein the
ring is
completed through another portion of the molecule (e.g., two substituents
together
form a ring);
(ii) substituted hydrocarbon substituents, that is, substituents containing
non-
hydrocarbon groups which, in the context of this invention, do not alter the
predominantly hydrocarbon nature of the substituent (e.g., halo (especially
chloro
and fluoro), hydroxy, alkoxy, mercapto, alkylmercapto, nitro, nitroso, and
sulphoxy);
(iii) hetero substituents, that is, substituents which, while having a
predominantly
hydrocarbon character, in the context of this invention, contain other than
carbon in
a ring or chain otherwise composed of carbon atoms.
[0083] Heteroatoms include sulfur, oxygen, nitrogen, and encompass
substituents as pyridyl, furyl, thienyl and imidazolyl. In general, no more
than two,
preferably no more than one, non-hydrocarbon substituent will be present for
every
ten carbon atoms in the hydrocarbyl group; typically, there will be no non-
hydrocarbon substituents in the hydrocarbyl group.
[0084] While the invention has been explained in relation to its
preferred
embodiments, it is to be understood that various modifications thereof will
become
apparent to those skilled in the art upon reading the specification.
Therefore, it is to
be understood that the invention disclosed herein is intended to cover such
modifications as fall within the scope of the appended claims.
21
