U.S. patent application number 16/680651 was filed with the patent office on 2020-05-28 for lubricating oil compositions with improved deposit resistance and methods thereof.
The applicant listed for this patent is ExxonMobil Research and Engineering Company. Invention is credited to Douglas E. Deckman, Willie A. Givens, Jr., Andrew D. Satterfield.
Application Number | 20200165537 16/680651 |
Document ID | / |
Family ID | 68848371 |
Filed Date | 2020-05-28 |
View All Diagrams
United States Patent
Application |
20200165537 |
Kind Code |
A1 |
Deckman; Douglas E. ; et
al. |
May 28, 2020 |
LUBRICATING OIL COMPOSITIONS WITH IMPROVED DEPOSIT RESISTANCE AND
METHODS THEREOF
Abstract
Provided is a lubricating oil composition and method of using
such a composition that provides for improved high temperature
deposit resistance. The composition includes a lubricating oil base
stock at from 20 to 95 wt % of the composition, at least one
ashless organic friction modifier at from 0.1 to 20 wt % of the
composition, and at least one overbased detergent at from 0.1 to 20
wt % of the composition. The remainder of composition includes one
or more other lubricating oil additives. The deposit resistance of
the lubricating oil composition as measured by TEOST 33C total
deposits is at least 20% lower than the deposit resistance for a
comparable lubricating oil composition not including the
combination of the at least one ashless organic friction modifier
and the at least one overbased detergent.
Inventors: |
Deckman; Douglas E.;
(Easton, PA) ; Satterfield; Andrew D.; (Furlong,
PA) ; Givens, Jr.; Willie A.; (Williamstown,
NJ) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ExxonMobil Research and Engineering Company |
Annandale |
NJ |
US |
|
|
Family ID: |
68848371 |
Appl. No.: |
16/680651 |
Filed: |
November 12, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62772360 |
Nov 28, 2018 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C10N 2010/04 20130101;
C10N 2010/04 20130101; C10N 2020/02 20130101; C10N 2010/04
20130101; C10N 2010/04 20130101; C10M 2223/045 20130101; C10M
2227/06 20130101; C10N 2030/02 20130101; C10M 2209/102 20130101;
C10M 2215/064 20130101; C10M 2219/046 20130101; C10M 2207/028
20130101; C10N 2030/06 20130101; C10N 2030/10 20130101; C10M
2203/1025 20130101; C10M 109/00 20130101; C10N 2020/02 20130101;
C10M 2215/08 20130101; C10N 2030/45 20200501; C10M 169/04 20130101;
C10M 2207/262 20130101; C10M 165/00 20130101; C10M 2207/046
20130101; C10N 2020/011 20200501; C10M 129/42 20130101; C10M
2223/045 20130101; C10M 141/00 20130101; C10M 2203/1006 20130101;
C10M 2203/1025 20130101; C10M 2207/262 20130101; C10M 2207/2855
20130101; C10M 2219/046 20130101; C10M 129/40 20130101; C10M
2207/028 20130101; C10M 2205/0285 20130101; C10N 2030/74 20200501;
C10M 2207/126 20130101; C10N 2010/04 20130101; C10M 2215/28
20130101; C10N 2030/52 20200501; C10M 163/00 20130101; C10N 2030/04
20130101; C10N 2040/25 20130101; C10M 2205/173 20130101; C10M
2207/289 20130101; C10M 2215/04 20130101 |
International
Class: |
C10M 169/04 20060101
C10M169/04; C10M 109/00 20060101 C10M109/00; C10M 129/40 20060101
C10M129/40; C10M 129/42 20060101 C10M129/42; C10M 141/00 20060101
C10M141/00 |
Claims
1. A lubricating oil composition comprising: a lubricating oil base
stock at from 20 to 95 wt % of the composition, at least one
ashless organic friction modifier at from 0.1 to 20 wt % of the
composition, at least one overbased detergent at from 0.1 to 20 wt
% of the composition, and wherein the remainder of the lubricating
oil composition includes one or more other lubricating oil
additives; wherein the at least one ashless organic friction
modifier is selected from the group consisting of ##STR00023##
wherein A and B are each independently H, a C1-C24 alkyl, or a
C2-C24 alkenyl; ##STR00024## wherein A, B and C are each
independently H, a C1-C24 alkyl, a C2-C24 alkenyl, a C1-C24
alkylcarbonyl, and a C1-C24 alkenylcarbonyl; ##STR00025## wherein A
is a C1-C24 alkyl, or a C2-C24 alkenyl and B is O, an amino, a
C1-C8 alkylamino or a C1-C8 dialkylamino; n-tallow 1,3
diaminopropane; a polymeric organic friction modifier containing
PIBSA, glycerol and oligomerized ethylene oxide and combinations
thereof; and wherein the deposit resistance as measured by TEOST
33C total deposits (ASTM D6335) is at least 20% lower than the
deposit resistance for a comparable lubricating oil composition not
including the combination of the at least one ashless organic
friction modifier and the at least one overbased detergent.
2. The composition of claim 1, wherein the lubricating oil base
stock is selected from the from the group consisting of a Group I
base stock, a Group II base stock, a Group III base stock, a Group
IV base stock, a Group V base stock and combinations thereof.
3. The composition of claim 1, wherein the lubricating oil base
stock is from 85 to 95 wt % of the lubricating oil composition.
4. The composition of claim 3, wherein the lubricating oil base
stock is selected from the group consisting of a 100N Group I base
stock, a 4.5 cSt Group II base stock, a 4 cSt gas to liquids (GTL)
base stock, a 4 cSt polyalphaolefin (PAO) base stock, a di-isononyl
phthalate ester base stock and combinations thereof.
5. The composition of claim 1, wherein the at least one overbased
detergent is metal containing detergent including sulfonates,
phenates, salicylates, carboxylates and combinations thereof and
having a Total Base Number (TBN) ranging between 60 and 600.
6. The composition of claim 5, wherein the at least one overbased
detergent is selected from the group consisting of 350 TBN calcium
salicylate, 400 TBN magnesium sulfonate, 400 TBN calcium sulfonate,
255 TBN calcium phenate, 68 TBN calcium salicylate and combinations
thereof.
7. The composition of claim 1, wherein the at least one ashless
organic friction modifier is selected from the group consisting of
mixed mono-(47%), di-(33%) and tri-(20%) fatty acids using
saturated C16 and C18 alkyl chains, glycerol mono-, di- and
tri-mixed oleate, propylene glycol stearyl ether,
poly-hydroxylcarboxylic acid esters of polyalkylene oxide modified
polyols, oleic acid, oleyl amide, and combinations thereof.
8. The composition of claim 7, wherein the at least one ashless
organic friction modifier is mixed mono-(47%), di-(33%) and
tri-(20%) fatty acids using saturated C16 and C18 alkyl chains at
from 0.1 to 2.0 wt % of the lubricating oil composition.
9. The composition of claim 1, wherein the deposit resistance as
measured by TEOST 33C total deposits (ASTM D6335) is less than or
equal to 75 mg.
10. The composition of claim 1, wherein the one or more other
lubricating oil additives are selected from the group consisting of
an anti-wear additive, viscosity index improver, antioxidant,
dispersant, pour point depressant, corrosion inhibitor, metal
deactivator, seal compatibility additive, anti-foam agent,
inhibitor, anti-rust additive, and ash forming metal containing
friction modifier.
11. The composition of claim 1, wherein the one or more other
lubricating oil additives range from 1 to 10 wt % of the
lubricating oil composition and include a combination of a
PIBSA/PAM dispersant, a C3/C6 secondary ZDDP antiwear additive, and
a diphenylamine antioxidant.
12. The composition of claim 1, wherein the lubricating oil base
stock has a kinematic viscosity at 100 deg. C. ranging from 2.5 to
12 cSt.
13. The composition of claim 1, wherein lubricating oil composition
is an SAE viscosity grade selected from the group consisting of
0W-30, 5W-30, 0W-20, 5W-20, 0W-16, 5W-16, 0W-12, 5W-12, 0W-8, and
5W-8.
14. The composition of claim 1, wherein the lubricating oil
composition is a passenger vehicle engine oil (PVEO) or a
commercial vehicle engine oil (CVEO).
15. A method for improving the high temperature deposit resistance
of a lubricating oil composition for use in lubricating a
mechanical component comprising: providing a lubricating oil
composition to a mechanical component, wherein the lubricating oil
composition comprises: a lubricating oil base stock at from 20 to
95 wt % of the composition, at least one ashless organic friction
modifier at from 0.1 to 20 wt % of the composition, at least one
overbased detergent at from 0.1 to 20 wt % of the composition, and
wherein the remainder of the lubricating oil composition includes
one or more other lubricating oil additives; wherein the at least
one ashless organic friction modifier is selected from the group
consisting of ##STR00026## wherein A and B are each independently
H, a C1-C24 alkyl, or a C2-C24 alkenyl; ##STR00027## wherein A, B
and C are each independently H, a C1-C24 alkyl, a C2-C24 alkenyl, a
C1-C24 alkylcarbonyl, and a C1-C24 alkenylcarbonyl; ##STR00028##
wherein A is a C1-C24 alkyl, or a C2-C24 alkenyl and B is O, an
amino, a C1-C8 alkylamino or a C1-C8 dialkylamino; n-tallow 1,3
diaminopropane; a polymeric organic friction modifier containing
PIBSA, glycerol and oligomerized ethylene oxide and combinations
thereof; and wherein the deposit resistance as measured by TEOST
33C total deposits (ASTM D6335) is at least 20% lower than the
deposit resistance for a comparable lubricating oil composition not
including the combination of the at least one ashless organic
friction modifier and the at least one overbased detergent.
16. The method of claim 15, wherein the lubricating oil base stock
is selected from the from the group consisting of a Group I base
stock, a Group II base stock, a Group III base stock, a Group IV
base stock, a Group V base stock and combinations thereof.
17. The method of claim 15, wherein the lubricating oil base stock
is from 85 to 95 wt % of the lubricating oil composition.
18. The method of claim 15, wherein the lubricating oil base stock
is selected from the group consisting of a 100N Group I base stock,
a 4.5 cSt Group II base stock, a 4 cSt gas to liquids (GTL) base
stock, a 4 cSt polyalphaolefin (PAO) base stock, a di-isononyl
phthalate ester base stock and combinations thereof.
19. The method of claim 15, wherein the at least one overbased
detergent is metal containing detergent including sulfonates,
phenates, salicylates, carboxylates and combinations thereof and
having a Total Base Number (TBN) ranging between 60 and 600.
20. The method of claim 19, wherein the at least one overbased
detergent is selected from the group consisting of 350 TBN calcium
salicylate, 400 TBN magnesium sulfonate, 400 TBN calcium sulfonate,
255 TBN calcium phenate, 68 TBN calcium salicylate and combinations
thereof.
21. The method of claim 15, wherein the at least one ashless
organic friction modifier is selected from the group consisting of
mixed mono-(47%), di-(33%) and tri-(20%) fatty acids using
saturated C16 and C18 alkyl chains, glycerol mono-, di- and
tri-mixed oleate, propylene glycol stearyl ether,
poly-hydroxylcarboxylic acid esters of polyalkylene oxide modified
polyols, oleic acid, oleyl amide, and combinations thereof.
22. The method of claim 21, wherein the at least one ashless
organic friction modifier is mixed mono-(47%), di-(33%) and
tri-(20%) fatty acids using saturated C16 and C18 alkyl chains at
from 0.1 to 2.0 wt % of the lubricating oil composition.
23. The method of claim 15, wherein the deposit resistance as
measured by TEOST 33C total deposits (ASTM D6335) is less than or
equal to 75 mg.
24. The method of claim 15, wherein the one or more other
lubricating oil additives are selected from the group consisting of
an anti-wear additive, viscosity index improver, antioxidant,
dispersant, pour point depressant, corrosion inhibitor, metal
deactivator, seal compatibility additive, anti-foam agent,
inhibitor, anti-rust additive, and ash forming metal containing
friction modifier.
25. The method of claim 24, wherein the one or more other
lubricating oil additives range from 1 to 10 wt % of the
lubricating oil composition and include a combination of a
PIBSA/PAM dispersant, a C3/C6 secondary ZDDP antiwear additive, and
a diphenylamine antioxidant.
26. The method of claim 15, wherein the lubricating oil base stock
has a kinematic viscosity at 100 deg. C. ranging from 2.5 to 12
cSt.
27. The method of claim 15, wherein the mechanical component is
selected from the group consisting of internal combustion engines,
power trains, drivelines, transmissions, gears, gear trains, gear
sets, compressors, pumps, hydraulic systems, bearings, bushings,
turbines, pistons, piston rings, cylinder liners, cylinders, cams,
tappets, lifters, bearings (journal, roller, tapered, needle,
ball), gears and valves.
28. The method of claim 27, wherein the mechanical component is an
internal combustion engine.
29. The method of claim 28, wherein lubricating oil composition is
an SAE viscosity grade selected from the group consisting of 0W-30,
5W-30, 0W-20, 5W-20, 0W-16, 5W-16, 0W-12, 5W-12, 0W-8, and
5W-8.
30. The method of claim 29, wherein the lubricating oil composition
is a passenger vehicle engine oil (PVEO) or a commercial vehicle
engine oil (CVEO).
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application No. 62/772,360, filed on Nov. 28, 2018, the entire
contents of which are incorporated herein by reference.
FIELD
[0002] This disclosure relates to lubricating oils with improved
deposit resistance and in particular, high temperature deposit
resistance, and methods of making and using such lubricating oils.
The lubricating oils include one or more ashless organic friction
modifiers in combination with one or more overbased detergents. The
lubricating oils are useful as passenger vehicle engine oil (PVEO)
products or commercial vehicle engine oil (CVEO) products.
BACKGROUND
[0003] Lubricating oils for internal combustion engines contain in
addition to at least one base lubricating oil, additives which
enhance the performance of the lubricating oil. A variety of
additives such as antioxidants, detergents, dispersants, friction
modifiers, viscosity modifiers, corrosion inhibitors, antiwear
additives, pour point depressants, seal swell additives, and
antifoam agents are used in lubricating oil compositions.
[0004] During engine operation, oil insoluble oxidation byproducts
are produced. Deposit formation in a lubricating oil will lead to
the deposits eventually falling out of the oil and depositing on
the surfaces for lubrication, which negatively impacts the
performance of the oil. Dispersants help keep these byproducts in
solution, thus diminishing their deposit on metal surfaces.
Dispersants may be ashless or ash-forming (non-ashless) in nature.
So called ashless dispersants are organic materials that form
substantially no ash upon combustion.
[0005] A known class of dispersants is the alkenylsuccinic
derivatives, typically produced by the reaction of a long chain
substituted alkenyl succinic compound, usually a substituted
succinic anhydride, with a polyhydroxy or polyamino compound. The
long chain group constituting the oleophilic portion of the
molecule which confers solubility in the oil, is normally a
polyisobutylene group. Many examples of this type of dispersant are
well known commercially and in the literature.
[0006] Engine cleanliness is a critical performance attribute of
modern engine lubricants. A well-known engine cleanliness test is
the TEOST 33C (ASTM D6335) deposit bench test, which is designed to
simulate temperatures experienced in turbochargers.
[0007] Auto builders are faced with challenging emission
requirements and CAFE requirements, and therefore are broadly
deploying turbocharged engines. Turbochargers are exposed to engine
exhaust gas and operate at speeds of 100,000 rpm or higher. As a
result of these operating conditions, generation of deposits on the
turbocharged engine surfaces greatly deteriorates engine
performance. Therefore, there is a need for lubricating oils that
when used with turbocharged passenger vehicle engines and
turbocharged commercial vehicle engines provide for an improvement
in high temperature deposit formation, deposit resistance and
cleanliness performance. There is also a need for lubricating oils
that provide for improvement cleanliness of mechanical components
lubricated by such oils.
SUMMARY
[0008] This disclosure relates to lubricating oils which provide
surprising and unexpected improvements in deposit resistance (in
particular high temperature deposit resistance) and cleanliness and
methods of making and using such lubricating oils. The lubricating
oils of this disclosure include one or more ashless organic
friction modifiers in combination with one or more overbased
detergents that provide improvements in cleanliness performance.
The disclosure also relates to methods of using such lubricating
oils to improve passenger vehicle engine and commercial vehicle
engine performance and in particular for turbocharged engines.
[0009] In one form the instant disclosure, a lubricating oil
composition comprises: a lubricating oil base stock at from 20 to
95 wt % of the composition, at least one ashless organic friction
modifier at from 0.1 to 20 wt % of the composition, at least one
overbased detergent at from 0.1 to 20 wt % of the composition, and
wherein the remainder of the lubricating oil composition includes
one or more other lubricating oil additives. The at least one
ashless organic friction modifier is selected from the group
consisting of
##STR00001##
wherein A and B are each independently H, a C1-C24 alkyl, or a
C2-C24 alkenyl;
##STR00002##
wherein A, B and C are each independently H, a C1-C24 alkyl, a
C2-C24 alkenyl, a C1-C24 alkylcarbonyl, and a C1-C24
alkenylcarbonyl;
##STR00003##
wherein A is a C1-C24 alkyl, or a C2-C24 alkenyl and B is O, an
amino, a C1-C8 alkylamino or a C1-C8 dialkylamino;
[0010] n-tallow 1,3 diaminopropane; a polymeric organic friction
modifier containing PIBSA, glycerol and oligomerized ethylene oxide
and combinations thereof. The deposit resistance of the lubricating
oil composition as measured by TEOST 33C total deposits (ASTM
D6335) is at least 20% lower than the deposit resistance for a
comparable lubricating oil composition not including the
combination of the at least one ashless organic friction modifier
and the at least one overbased detergent.
[0011] In another form the instant disclosure, a method for
improving the high temperature deposit resistance of a lubricating
oil composition for use in lubricating a mechanical component
comprises: providing a lubricating oil composition to a mechanical
component, wherein the lubricating oil composition comprises: a
lubricating oil base stock at from 20 to 95 wt % of the
composition, at least one ashless organic friction modifier at from
0.1 to 20 wt % of the composition, at least one overbased detergent
at from 0.1 to 20 wt % of the composition, and wherein the
remainder of the lubricating oil composition includes one or more
other lubricating oil additives. The at least one ashless organic
friction modifier is selected from the group consisting of
##STR00004##
wherein A and B are each independently H, a C1-C24 alkyl, or a
C2-C24 alkenyl;
##STR00005##
wherein A, B and C are each independently H, a C1-C24 alkyl, a
C2-C24 alkenyl, a C1-C24 alkylcarbonyl, and a C1-C24
alkenylcarbonyl;
##STR00006##
wherein A is a C1-C24 alkyl, or a C2-C24 alkenyl and B is O, an
amino, a C1-C8 alkylamino or a C1-C8 dialkylamino;
[0012] n-tallow 1,3 diaminopropane; a polymeric organic friction
modifier containing PIBSA, glycerol and oligomerized ethylene oxide
and combinations thereof. The method provides a deposit resistance
as measured by TEOST 33C total deposits (ASTM D6335) that is at
least 20% lower than the deposit resistance for a comparable
lubricating oil composition not including the combination of the at
least one ashless organic friction modifier and the at least one
overbased detergent.
[0013] Other objects and advantages of the present disclosure will
become apparent from the detailed description and drawings that
follow.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 shows a tabular depiction of TEOST 33C results for
partially formulated lubricating oil compositions of the Examples
including various base stocks and combinations of high TBN calcium
salicylate detergent and ashless organic friction modifier.
[0015] FIG. 2 shows a tabular depiction of TEOST 33C results for
partially formulated lubricating oil compositions of the Examples
including a combination of various high TBN detergents and ashless
organic friction modifier with a 4 cSt PAO base stock.
[0016] FIG. 3 shows a tabular depiction of TEOST 33C results for
partially formulated lubricating oil compositions of the Examples
including various friction modifiers in combination with a high TBN
calcium salicylate detergent in a 4 cSt PAO base stock.
[0017] FIG. 4 shows a tabular depiction of TEOST 33C results for
partially formulated lubricating oil compositions of the Examples
including a combination of high TBN calcium salicylate detergent in
combination with an ashless organic friction modifier at various
loadings (0 to 1 wt. % of the partially formulated oil) in a 4 cSt
PAO base stock.
[0018] FIG. 5 shows a graphical depiction of TEOST 33C results
versus ashless organic friction modifier loading for the partially
formulated lubricating oil compositions of the Examples of FIG.
4.
DETAILED DESCRIPTION
Definitions
[0019] "About" or "approximately." All numerical values within the
detailed description and the claims herein are modified by "about"
or "approximately" the indicated value, and take into account
experimental error and variations that would be expected by a
person having ordinary skill in the art.
[0020] "Alkyl" as it relates to the ashless organic friction
modifiers includes straight-chain or branched alkyl groups, such
as, methyl, ethyl, n-propyl, i-propyl or the different butyl,
pentyl or hexyl isomers.
[0021] "Alkenyl" as it relates to the ashless organic friction
modifiers includes straight-chain or branched alkenes such as
ethenyl, 1-propenyl, 2-propenyl, and the different butenyl,
pentenyl and hexenyl isomers.
[0022] "Alkylcarbonyl" as it relates to the ashless organic
friction modifiers denotes a straight-chain or branched alkyl
moieties bonded to a C(.dbd.O) moiety. Examples of "alkylcarbonyl"
include CH.sub.3C(.dbd.O)--, CH.sub.3CH.sub.2CH.sub.2C).dbd.O)--
and (CH.sub.3).sub.2CHC(.dbd.O)--.
[0023] "Major amount" as it relates to components included within
the lubricating oils of the specification and the claims means
greater than or equal to 50 wt. %, or greater than or equal to 60
wt. %, or greater than or equal to 70 wt. %, or greater than or
equal to 80 wt. %, or greater than or equal to 90 wt. % based on
the total weight of the lubricating oil.
[0024] "Minor amount" as it relates to components included within
the lubricating oils of the specification and the claims means less
than 50 wt. %, or less than or equal to 40 wt. %, or less than or
equal to 30 wt. %, or greater than or equal to 20 wt. %, or less
than or equal to 10 wt. %, or less than or equal to 5 wt. %, or
less than or equal to 2 wt. %, or less than or equal to 1 wt. %,
based on the total weight of the lubricating oil.
[0025] "Essentially free" as it relates to components included
within the lubricating oils of the specification and the claims
means that the particular component is at 0 weight % within the
lubricating oil, or alternatively is at impurity type levels within
the lubricating oil (less than 100 ppm, or less than 20 ppm, or
less than 10 ppm, or less than 1 ppm).
[0026] "Other lubricating oil additives" as used in the
specification and the claims means other lubricating oil additives
that are not specifically recited in the particular section of the
specification or the claims. For example, other lubricating oil
additives may include, but are not limited to, antioxidants,
detergents, dispersants, antiwear additives, corrosion inhibitors,
viscosity modifiers, metal passivators, pour point depressants,
seal compatibility agents, antifoam agents, extreme pressure
agents, friction modifiers and combinations thereof.
[0027] "Hydrocarbon" refers to a compound consisting of carbon
atoms and hydrogen atoms.
[0028] "Alkane" refers to a hydrocarbon that is completely
saturated. An alkane can be linear, branched, cyclic, or
substituted cyclic.
[0029] "Olefin" refers to a non-aromatic hydrocarbon comprising one
or more carbon-carbon double bond in the molecular structure
thereof.
[0030] "Mono-olefin" refers to an olefin comprising a single
carbon-carbon double bond.
[0031] "Cn" group or compound refers to a group or a compound
comprising carbon atoms at total number thereof of n. Thus, "Cm-Cn"
group or compound refers to a group or compound comprising carbon
atoms at a total number thereof in the range from m to n. Thus, a
C1-C50 alkyl group refers to an alkyl group comprising carbon atoms
at a total number thereof in the range from 1 to 50.
[0032] "Carbon backbone" refers to the longest straight carbon
chain in the molecule of the compound or the group in question.
"Branch" refer to any substituted or unsubstituted hydrocarbyl
group connected to the carbon backbone. A carbon atom on the carbon
backbone connected to a branch is called a "branched carbon."
[0033] "Epsilon-carbon" in a branched alkane refers to a carbon
atom in its carbon backbone that is (i) connected to two hydrogen
atoms and two carbon atoms and (ii) connected to a branched carbon
via at least four (4) methylene (CH.sub.2) groups. Quantity of
epsilon carbon atoms in terms of mole percentage thereof in a
alkane material based on the total moles of carbon atoms can be
determined by using, e.g., .sup.13C NMR.
[0034] "SAE" refers to SAE International, formerly known as Society
of Automotive Engineers, which is a professional organization that
sets standards for internal combustion engine lubricating oils.
[0035] "SAE J300" refers to the viscosity grade classification
system of engine lubricating oils established by SAE, which defines
the limits of the classifications in rheological terms only.
[0036] "Base stock" or "base oil" interchangeably refers to an oil
that can be used as a component of lubricating oils, heat transfer
oils, hydraulic oils, grease products, and the like.
[0037] "Lubricating oil" or "lubricant" interchangeably refers to a
substance that can be introduced between two or more surfaces to
reduce the level of friction between two adjacent surfaces moving
relative to each other. A lubricant base stock is a material,
typically a fluid at various levels of viscosity at the operating
temperature of the lubricant, used to formulate a lubricant by
admixing with other components. Non-limiting examples of base
stocks suitable in lubricants include API Group I, Group II, Group
III, Group IV, and Group V base stocks. PAOs, particularly
hydrogenated PAOs, have recently found wide use in lubricants as a
Group IV base stock, and are particularly preferred. If one base
stock is designated as a primary base stock in the lubricant,
additional base stocks may be called a co-base stock.
[0038] All kinematic viscosity values in this disclosure are as
determined pursuant to ASTM D445. Kinematic viscosity at
100.degree. C. is reported herein as KV100, and kinematic viscosity
at 40.degree. C. is reported herein as KV40. Unit of all KV100 and
KV40 values herein is cSt unless otherwise specified.
[0039] All viscosity index ("VI") values in this disclosure are as
determined pursuant to ASTM D2270.
[0040] All Noack volatility ("NV") values in this disclosure are as
determined pursuant to ASTM D5800 unless specified otherwise. Unit
of all NV values is wt %, unless otherwise specified.
[0041] All pour point values in this disclosure are as determined
pursuant to ASTM D5950 or D97.
[0042] All CCS viscosity ("CCSV") values in this disclosure are as
determined pursuant to ASTM 5293. Unit of all CCSV values herein is
millipascal second (mPas), which is equivalent to centipoise),
unless specified otherwise. All CCSV values are measured at a
temperature of interest to the lubricating oil formulation or oil
composition in question. Thus, for the purpose of designing and
fabricating engine oil formulations, the temperature of interest is
the temperature at which the SAE J300 imposes a minimal CCSV.
[0043] All percentages in describing chemical compositions herein
are by weight unless specified otherwise. "Wt. %" means percent by
weight.
Lubricating Oil Compositions and Methods of this Disclosure
[0044] It has been surprisingly found that, in accordance with this
disclosure deposit resistance (in particular high temperature
deposit resistance) and engine cleanliness are improved for
lubricating oils including one or more ashless organic friction
modifiers in combination with one or more overbased detergents in
comparison to comparable lubricating oils not including the
combinations of one or more ashless organic friction modifiers and
one or more overbased detergents disclosed herein.
[0045] In particular, it has been surprisingly found that, for
lubricating oils of this disclosure containing a lubricating oil
base stock at from 20 to 95 wt % of the composition, at least one
ashless organic friction modifier at from 0.1 to 20 wt % of the
composition, at least one overbased detergent at from 0.1 to 20 wt
% of the composition, and wherein the remainder of the lubricating
oil composition includes one or more other lubricating oil
additives provide for a deposit resistance as measured by TEOST 33C
total deposits (ASTM D6335) that is at least 20% lower than the
deposit resistance for a comparable lubricating oil composition not
including the combination of the at least one ashless organic
friction modifier and the at least one overbased detergent.
[0046] The at least one ashless organic friction modifier may be
selected from the group consisting of
##STR00007##
wherein A and B are each independently H, a C1-C24 alkyl, or a
C2-C24 alkenyl;
##STR00008##
wherein A, B and C are each independently H, a C1-C24 alkyl, a
C2-C24 alkenyl, a C1-C24 alkylcarbonyl, and a C1-C24
alkenylcarbonyl;
##STR00009##
wherein A is a C1-C24 alkyl, or a C2-C24 alkenyl and B is O, an
amino, a C1-C8 alkylamino or a C1-C8 dialkylamino;
[0047] n-tallow 1,3 diaminopropane; a polymeric organic friction
modifier containing PIBSA, glycerol and oligomerized ethylene oxide
and combinations thereof.
[0048] For the at least one ashless organic friction modifier, it
is preferable if it is selected from the group consisting of mixed
mono-(47%), di-(33%) and tri-(20%) fatty acids using saturated C16
and C18 alkyl chains, glycerol mono-, di- and tri-mixed oleate,
propylene glycol stearyl ether, poly-hydroxylcarboxylic acid esters
of polyalkylene oxide modified polyols, n-tallow 1,3
diaminopropane, oleic acid, oleyl amide, and polymeric organic
friction modifier containing PIBSA, glycerol and oligomerized
ethylene oxide and combinations thereof.
[0049] In alternative forms, the deposit resistance as measured by
TEOST 33C total deposits (ASTM D6335) of the lubricating oil
compositions disclosed herein is at least 100% lower, or at least
90% lower, or at least 80% lower, or at least 70% lower, or at
least 60% lower, or at least 50% lower, or at least 40% lower, or
at least 30% lower, or at least 10% lower than a comparable
lubricating oil composition not including the combination of one or
more ashless organic friction modifiers and one or more overbased
detergents disclosed herein.
[0050] The lubricating oil compositions disclosed herein provide a
TEOST 33C deposits of less than or equal to 80 mg, or less than or
equal to 70 mg, or less than or equal to 60 mg, or less than or
equal to 50 mg, or less than or equal to 40 mg, or less than or
equal to 30 mg, or less than or equal to 20 mg, or less than or
equal to 10 mg. The benefit in TEOST 33C deposits (lower TEOST 33C
values) provided by the lubricating oil compositions including one
or more ashless organic friction modifiers in combination with one
or more overbased detergents in comparison to comparable
lubricating oil compositions not including the combinations of one
or more ashless organic friction modifiers and one or more
overbased detergents disclosed is surprising and unexpected.
[0051] In accordance with this disclosure, a method is also
provided to improve the high temperature deposit resistance of a
lubricating oil composition for use in lubricating a mechanical
component comprising: providing a lubricating oil composition to a
mechanical component, wherein the lubricating oil composition
comprises: a lubricating oil base stock at from 20 to 95 wt % of
the composition, at least one ashless organic friction modifier at
from 0.1 to 20 wt % of the composition, at least one overbased
detergent at from 0.1 to 20 wt % of the composition, and wherein
the remainder of the lubricating oil composition includes one or
more other lubricating oil additives. The method provides for a
deposit resistance as measured by TEOST 33C total deposits (ASTM
D6335) that is at least 20% lower than the deposit resistance for a
comparable lubricating oil composition not including the
combination of the at least one ashless organic friction modifier
and the at least one overbased detergent. The at least one ashless
organic friction modifier may be selected from the group consisting
of
##STR00010##
wherein A and B are each independently H, a C1-C24 alkyl, or a
C2-C24 alkenyl;
##STR00011##
wherein A, B and C are each independently H, a C1-C24 alkyl, a
C2-C24 alkenyl, a C1-C24 alkylcarbonyl, and a C1-C24
alkenylcarbonyl;
##STR00012##
wherein A is a C1-C24 alkyl, or a C2-C24 alkenyl and B is O, an
amino, a C1-C8 alkylamino or a C1-C8 dialkylamino;
[0052] n-tallow 1,3 diaminopropane; a polymeric organic friction
modifier containing PIBSA, glycerol and oligomerized ethylene oxide
and combinations thereof.
[0053] For the at least one ashless organic friction modifier, it
is preferable that it is selected from the group consisting of
mixed mono-(47%), di-(33%) and tri-(20%) fatty acids using
saturated C16 and C18 alkyl chains, glycerol mono-, di- and
tri-mixed oleate, propylene glycol stearyl ether,
poly-hydroxylcarboxylic acid esters of polyalkylene oxide modified
polyols, n-tallow 1,3 diaminopropane, oleic acid, oleyl amide, and
polymeric organic friction modifier containing PIBSA, glycerol and
oligomerized ethylene oxide and combinations thereof.
[0054] The method to improve high temperature deposit resistance of
a lubricating oil composition for use in lubricating a mechanical
component provides a TEOST 33C deposits of less than or equal to 80
mg, or less than or equal to 70 mg, or less than or equal to 60 mg,
or less than or equal to 50 mg, or less than or equal to 40 mg, or
less than or equal to 30 mg, or less than or equal to 20 mg, or
less than or equal to 10 mg. The benefit in TEOST 33C deposits
(lower TEOST 33C values) provided by the methods to improve high
temperature deposit resistance of a lubricating oil composition
including one or more ashless organic friction modifiers in
combination with one or more overbased detergents in comparison to
comparable lubricating oil compositions not including the
combinations of one or more ashless organic friction modifiers and
one or more overbased detergents disclosed is surprising and
unexpected.
[0055] The methods to improve deposit resistance of this disclosure
provide advantaged cleanliness performance in the lubrication of
internal combustion engines, power trains, drivelines,
transmissions, gears, gear trains, gear sets, compressors, pumps,
hydraulic systems, bearings, bushings, turbines, and the like.
Also, the methods to improve deposit resistance of this disclosure
provide advantaged cleanliness performance in the lubrication of
mechanical components, which can include, for example, pistons,
piston rings, cylinder liners, cylinders, cams, tappets, lifters,
bearings (journal, roller, tapered, needle, ball, and the like),
gears, valves, and the like. Further, the lubricating oil
compositions of this disclosure provide advantaged cleanliness
performance and deposit resistance as a component in lubricant
compositions, which can include, for example, lubricating liquids,
semi-solids, solids, greases, dispersions, suspensions, material
concentrates, additive concentrates, and the like.
Friction Modifiers
[0056] A friction modifier is any material or materials that can
alter the coefficient of friction of a surface lubricated by any
lubricant or fluid containing such material(s). Friction modifiers,
also known as friction reducers, friction improvers, or lubricity
agents or oiliness agents, and other such agents that change the
ability of base oils, formulated lubricant compositions, or
functional fluids, to modify the coefficient of friction of a
lubricated surface may be effectively used in combination with the
base oils or lubricant compositions of the present disclosure if
desired. Friction modifiers that lower the coefficient of friction
are particularly advantageous in combination with the base oils and
lube compositions of this disclosure.
[0057] Ashless organic friction modifiers are in included in the
lubricating oil compositions of this disclosure. In particular, the
inventive lubricating oils of this disclosure include at least one
ashless organic friction modifier, which is incorporated at from
0.01 to 20 wt %, or 0.05 to 18 wt %, or 0.1 to 15 wt %, or 0.3 to
10 wt %, or 0.5 to 5 wt %, or 0.6 to 4 wt %, or 0.7 to 3 wt %, or
0.8 to 2.5 wt %, or 0.9 to 2.0 wt %, or 1.0 to 1.5 wt % of the
lubricating oil composition.
[0058] Ashless organic friction modifiers useful in this disclosure
may include lubricant materials that contain effective amounts of
polar groups, for example, hydroxyl-containing hydrocarbyl base
oils, glycerides, partial glycerides, glyceride derivatives, and
the like. Polar groups in friction modifiers may include
hydrocarbyl groups containing effective amounts of 0, N, S, or P,
individually or in combination. Other friction modifiers that may
be particularly effective include, for example, salts (both
ash-containing and ashless derivatives) of fatty acids, fatty
alcohols, fatty amides, fatty esters, hydroxyl-containing
carboxylates, and comparable synthetic long-chain hydrocarbyl
acids, alcohols, amides, esters, hydroxy carboxylates, and the
like. In some instances fatty organic acids, fatty amines, and
sulfurized fatty acids may be used as suitable friction
modifiers.
[0059] Other illustrative friction modifiers useful in the
lubricating engine oil formulations of this disclosure include, for
example, alkoxylated fatty acid esters, alkanolamides, polyol fatty
acid esters, borated glycerol fatty acid esters, fatty alcohol
ethers, and mixtures thereof.
[0060] Illustrative alkoxylated fatty acid esters include, for
example, polyoxyethylene stearate, fatty acid polyglycol ester, and
the like. These can include polyoxypropylene stearate,
polyoxybutylene stearate, polyoxyethylene isosterate,
polyoxypropylene isostearate, polyoxyethylene palmitate, and the
like.
[0061] Illustrative alkanolamides include, for example, lauric acid
diethylalkanolamide, palmic acid diethylalkanolamide, and the like.
These can include oleic acid diethyalkanolamide, stearic acid
diethylalkanolamide, oleic acid diethylalkanolamide,
polyethoxylated hydrocarbylamides, polypropoxylated
hydrocarbylamides, and the like.
[0062] Illustrative polyol fatty acid esters include, for example,
glycerol mono-oleate, glycerol mono-, di- and tri-mixed oleate,
saturated mono-, di-, and tri-glyceride esters, glycerol
mono-stearate, and the like. These can include polyol esters,
hydroxyl-containing polyol esters, and the like.
[0063] Illustrative borated glycerol fatty acid esters include, for
example, borated glycerol mono-oleate, borated glycerol mono-, di-
and tri-mixed oleate, borated saturated mono-, di-, and
tri-glyceride esters, borated glycerol mono-sterate, and the like.
In addition to glycerol polyols, these can include
trimethylolpropane, pentaerythritol, sorbitan, and the like. These
esters can be polyol monocarboxylate esters, polyol dicarboxylate
esters, and on occasion polyoltricarboxylate esters. Preferred can
be the glycerol mono-oleates, glycerol dioleates, glycerol
trioleates, glycerol mono-, di- and tri-mixed oleates, glycerol
monostearates, glycerol distearates, and glycerol tristearates and
the corresponding glycerol monopalmitates, glycerol dipalmitates,
and glycerol tripalmitates, and the respective isostearates,
linoleates, and the like. On occasion the glycerol esters can be
preferred as well as mixtures containing any of these. Ethoxylated,
propoxylated, butoxylated fatty acid esters of polyols, especially
using glycerol as underlying polyol can be preferred.
[0064] Illustrative fatty alcohol ethers include, for example,
stearyl ether, myristyl ether, and the like. Alcohols, including
those that have carbon numbers from C3 to C50, can be ethoxylated,
propoxylated, or butoxylated to form the corresponding fatty alkyl
ethers. The underlying alcohol portion can preferably be stearyl,
myristyl, C.sub.11-C.sub.13 hydrocarbon, oleyl, isosteryl, and the
like.
[0065] In certain embodiments, the friction modifier comprises at
least one of a long chain alkly thiocarbamide, mixed glyceride
ester (substituted or unsubstituted), ethoxylated fatty ester,
phenyl, or combination thereof. In certain embodiments, the
friction modifier is selected from the group consisting of a
molybdenum-containing friction modifier (long chain alkyl thio
carbamide molybdenum complex), a mono, di and/or trimester; mostly
saturated C14, C16 & C18; an ethoxylated fatty ester; an
ester/ether block copolymer, and combinations thereof.
[0066] Advantageous ashless organic friction modifiers for the
lubricating oil compositions of the instant disclosure include the
following:
##STR00013##
wherein A and B are each independently H, a C1-C24 alkyl, or a
C2-C24 alkenyl.
[0067] In a preferable form of structure (1), A is CH.sub.3 and B
is a C16-C20 alkyl group.
##STR00014##
wherein A, B and C are each independently H, a C1-C24 alkyl, a
C2-C24 alkenyl, a C1-C24 alkylcarbonyl, and a C1-C24
alkenylcarbonyl.
[0068] In a preferable form of structure (2), A is a C14-C20
alkylcarbonyl or a C14-C20 alkenylcarbonyl
##STR00015##
wherein A is a C1-C24 alkyl, or a C2-C24 alkenyl and B is O, an
amino, a C1-C8 alkylamino or a C1-C8 dialkylamino.
[0069] In a preferable form of structure (3), A is a C14-C20 alkyl
or a C14-C20 alkenyl and B is oxygen.
[0070] Preferred ashless friction modifiers for the lubricating oil
compositions of the instant disclosure include mixed mono-(47%),
di-(33%) and tri-(20%) fatty acids using saturated C16 and C18
alkyl chains), a glycerol mono-, di- and tri-mixed oleate, a
propylene glycol stearyl ether, a poly-hydroxylcarboxylic acid
esters of polyalkylene oxide modified polyols, n-tallow 1,3
diaminopropane, oleic acid, oleyl amide, and a polymeric organic
friction modifier containing PIBSA, glycerol and oligomerized
ethylene oxide.
[0071] Other optional non-ashless (ash forming) inorganic friction
modifiers for use in combination with the at least one ashless
organic friction modifier may include metal-containing compounds in
combination with the ashless organic friction modifiers disclosed
herein. Illustrative metal-containing friction modifiers may
include, for example, inorganic compounds or materials, or mixtures
thereof. Illustrative optional inorganic friction modifiers useful
in the lubricating engine oil formulations of this disclosure
include, for example, molybdenum amine, molybdenum diamine, an
organotungstenate, a molybdenum dithiocarbamate, molybdenum
dithiophosphates, molybdenum amine complexes, molybdenum
carboxylates, and the like, and mixtures thereof. Similar tungsten
based compounds may be preferable.
[0072] Optional non-ashless (ash forming) metal-containing
inorganic friction modifiers may include metal salts or
metal-ligand complexes where the metals may include alkali,
alkaline earth, or transition group metals. Such metal-containing
friction modifiers may also have low-ash characteristics.
Transition metals may include Mo, Sb, Sn, Fe, Cu, Zn, and others.
Ligands may include hydrocarbyl derivative of alcohols, polyols,
glycerols, partial ester glycerols, thiols, carboxylates,
carbamates, thiocarbamates, dithiocarbamates, phosphates,
thiophosphates, dithiophosphates, amides, imides, amines,
thiazoles, thiadiazoles, dithiazoles, diazoles, triazoles, and
other polar molecular functional groups containing effective
amounts of O, N, S, or P, individually or in combination. In
particular, Mo-containing compounds can be particularly effective
such as for example Mo-dithiocarbamates, Mo(DTC),
Mo-dithiophosphates, Mo(DTP), Mo-amines, Mo (Am), Mo-alcoholates,
Mo-alcohol-amides, etc. See U.S. Pat. Nos. 5,824,627; 6,232,276;
6,153,564; 6,143,701; 6,110,878; 5,837,657; 6,010,987; 5,906,968;
6,734,150; 6,730,638; 6,689,725; 6,569,820; WO 99/66013; WO
99/47629; WO 98/26030.
[0073] Useful concentrations of optional non-ashless (ash forming)
friction modifiers may range from 0.01 weight percent to 5 weight
percent, or about 0.1 weight percent to about 2.5 weight percent,
or about 0.1 weight percent to about 1.5 weight percent, or about
0.1 weight percent to about 1 weight percent. Concentrations of
molybdenum-containing materials are often described in terms of Mo
metal concentration. Advantageous concentrations of Mo may range
from 25 ppm to 700 ppm or more, and often with a preferred range of
50-200 ppm. Friction modifiers of all types may be used in mixtures
with the ashless organic friction modifiers of this disclosure.
Often to mixtures of two or more friction modifiers, or mixtures of
friction modifier(s) with alternate surface active material(s), are
also desirable.
Detergents
[0074] Illustrative detergents useful in the lubricating oil
compositions of this disclosure include, for example, alkali metal
detergents, alkaline earth metal detergents, or mixtures of one or
more alkali metal detergents and one or more alkaline earth metal
detergents. A typical detergent is an anionic material that
contains a long chain hydrophobic portion of the molecule and a
smaller anionic or oleophobic hydrophilic portion of the molecule.
The anionic portion of the detergent is typically derived from an
organic acid such as a sulfur-containing acid, carboxylic acid
(e.g., salicylic acid), phosphorus-containing acid, phenol, or
mixtures thereof. The counterion is typically an alkaline earth or
alkali metal. The detergent can be overbased as described
herein.
[0075] The detergent is preferably a metal salt of an organic or
inorganic acid, a metal salt of a phenol, or mixtures thereof. The
metal is preferably selected from an alkali metal, an alkaline
earth metal, and mixtures thereof. The organic or inorganic acid is
selected from an aliphatic organic or inorganic acid, a
cycloaliphatic organic or inorganic acid, an aromatic organic or
inorganic acid, and mixtures thereof.
[0076] The metal is preferably selected from an alkali metal, an
alkaline earth metal, and mixtures thereof. More preferably, the
metal is selected from calcium (Ca), magnesium (Mg), and mixtures
thereof.
[0077] The organic acid or inorganic acid is preferably selected
from a sulfur-containing acid, a carboxylic acid, a
phosphorus-containing acid, and mixtures thereof.
[0078] Preferably, the metal salt of an organic or inorganic acid
or the metal salt of a phenol comprises calcium phenate, calcium
sulfonate, calcium salicylate, magnesium phenate, magnesium
sulfonate, magnesium salicylate, an overbased detergent, and
mixtures thereof.
[0079] Salts that contain a substantially stochiometric amount of
the metal are described as neutral salts and have a total base
number (TBN, as measured by ASTM D2896) of from 0 to 80. Many
compositions are overbased, containing large amounts of a metal
base that is achieved by reacting an excess of a metal compound (a
metal hydroxide or oxide, for example) with an acidic gas (such as
carbon dioxide). Useful detergents can be neutral, mildly
overbased, or highly overbased. These detergents can be used in
mixtures of neutral, overbased, highly overbased calcium
salicylate, sulfonates, phenates and/or magnesium salicylate,
sulfonates, phenates. The TBN ranges can vary from low, medium to
high TBN products, including as low as 0 to as high as 600.
Preferably the TBN delivered by the detergent is between 60 and
600, more preferably between 200 and 500, and even more preferably
between 250 and 450. Mixtures of low, medium, high TBN can be used,
along with mixtures of calcium and magnesium metal based
detergents, and including sulfonates, phenates, salicylates, and
carboxylates. A detergent mixture with a metal ratio of 1, in
conjunction of a detergent with a metal ratio of 2, and as high as
a detergent with a metal ratio of 5, can be used. Borated
detergents can also be used.
[0080] Alkaline earth phenates are another useful class of
detergent. These detergents can be made by reacting alkaline earth
metal hydroxide or oxide (CaO, Ca(OH).sub.2, BaO, Ba(OH).sub.2,
MgO, Mg(OH).sub.2, for example) with an alkyl phenol or sulfurized
alkylphenol. Useful alkyl groups include straight chain or branched
C.sub.1-C.sub.30 alkyl groups, preferably, C.sub.4-C.sub.20 or
mixtures thereof. Examples of suitable phenols include
isobutylphenol, 2-ethylhexylphenol, nonylphenol, dodecyl phenol,
and the like. It should be noted that starting alkylphenols may
contain more than one alkyl substituent that are each independently
straight chain or branched and can be used from 0.5 to 6 weight
percent. When a non-sulfurized alkylphenol is used, the sulfurized
product may be obtained by methods well known in the art. These
methods include heating a mixture of alkylphenol and sulfurizing
agent (including elemental sulfur, sulfur halides such as sulfur
dichloride, and the like) and then reacting the sulfurized phenol
with an alkaline earth metal base.
[0081] In accordance with this disclosure, metal salts of
carboxylic acids are preferred detergents. These carboxylic acid
detergents may be prepared by reacting a basic metal compound with
at least one carboxylic acid and removing free water from the
reaction product. These compounds may be overbased to produce the
desired TBN level. Detergents made from salicylic acid are one
preferred class of detergents derived from carboxylic acids. Useful
salicylates include long chain alkyl salicylates. One useful family
of compositions is of the formula
##STR00016##
where R is an alkyl group having 1 to about 30 carbon atoms, n is
an integer from 1 to 4, and M is an alkaline earth metal. Preferred
R groups are alkyl chains of at least C.sub.11, preferably C.sub.13
or greater. R may be optionally substituted with substituents that
do not interfere with the detergent's function. M is preferably,
calcium, magnesium, barium, or mixtures thereof. More preferably, M
is calcium.
[0082] Hydrocarbyl-substituted salicylic acids may be prepared from
phenols by the Kolbe reaction (see U.S. Pat. No. 3,595,791). The
metal salts of the hydrocarbyl-substituted salicylic acids may be
prepared by double decomposition of a metal salt in a polar solvent
such as water or alcohol.
[0083] Alkaline earth metal phosphates are also used as detergents
and are known in the art.
[0084] Detergents may be simple detergents or what is known as
hybrid or complex detergents. The latter detergents can provide the
properties of two detergents without the need to blend separate
materials. See U.S. Pat. No. 6,034,039.
[0085] Preferred detergents include calcium sulfonates, magnesium
sulfonates, calcium salicylates, magnesium salicylates, calcium
phenates, magnesium phenates, and other related components
(including borated detergents), and mixtures thereof. Preferred
mixtures of detergents include magnesium sulfonate and calcium
salicylate, magnesium sulfonate and calcium sulfonate, magnesium
sulfonate and calcium phenate, calcium phenate and calcium
salicylate, calcium phenate and calcium sulfonate, calcium phenate
and magnesium salicylate, calcium phenate and magnesium phenate.
Overbased detergents are also preferred in terms of having a high
TBN in the range of between 200 and 600. A particularly preferred
detergent for the lubricating oil compositions of the instant
disclosure is a 350 TBN calcium salicylate. A 400 TBN magnesium
sulfonate, a 400 TBN calcium sulfonate, a 255 TBN calcium phenate
and a 68 TBN calcium salicylate detergent have also provided
advantageous performance in the lubricating oil compositions of the
instant disclosure.
[0086] The detergent concentration in the lubricating oil
compositions of this disclosure can range from 0.1 to 20 wt %, or
0.2 to 15 wt %, or 0.3 to 10 wt %, or 0.4 to 8.0 wt %, or 0.5 to
6.0 wt %, or 0.8 to 4 wt %, or 1.0 to 3.0 wt %, or 1.2 to 2.5 wt %,
or 1.5 to 2.0 wt %, based on the total weight of the lubricating
oil composition.
[0087] As used herein, the detergent concentrations are given on an
"as delivered" basis. Typically, the active detergent is delivered
with a process oil. The "as delivered" detergent typically contains
from about 20 weight percent to about 100 weight percent, or from
about 40 weight percent to about 60 weight percent, of active
detergent in the "as delivered" detergent product.
Lubricating Oil Base Stocks
[0088] A wide range of lubricating oil base stocks can be used in
conjunction with the at least one organic ashless friction modifier
and the at least one over based detergent of the lubricating oils
disclosed herein. Such base stocks can be either derived from
natural resources or synthetic, including un-refined, refined, or
re-refined oils. Un-refined oil base stocks include shale oil
obtained directly from retorting operations, petroleum oil obtained
directly from primary distillation, and ester oil obtained directly
from a natural source (such as plant matters and animal tissues) or
directly from a chemical esterification process. Refined oil base
stocks are those un-refined base stocks further subjected to one or
more purification steps such as solvent extraction, secondary
distillation, acid extraction, base extraction, filtration, and
percolation to improve the at least one lubricating oil property.
Re-refined oil base stocks are obtained by processes analogous to
refined oils but using an oil that has been previously used as a
feed stock.
[0089] Groups I, II, III, IV and V are broad base oil stock
categories developed and defined by the American Petroleum
Institute (API Publication 1509; www.API.org) to create guidelines
for lubricant base oils. Group I base stocks have a viscosity index
of between about 80 to 120 and contain greater than about 0.03%
sulfur and/or less than about 90% saturates. Group II base stocks
have a viscosity index of between about 80 to 120, and contain less
than or equal to about 0.03% sulfur and greater than or equal to
about 90% saturates. Group III stocks have a viscosity index
greater than about 120 and contain less than or equal to about
0.03% sulfur and greater than about 90% saturates. Group IV
includes polyalphaolefins (PAO). Group V base stock includes base
stocks not included in Groups I-IV. The table below summarizes
properties of each of these five groups.
TABLE-US-00001 Base Oil Properties Saturates Sulfur Viscosity Index
Group I <90 and/or >0.03% and .gtoreq.80 and <120 Group II
.gtoreq.90 and .ltoreq.0.03% and .gtoreq.80 and <120 Group III
.gtoreq.90 and .ltoreq.0.03% and .gtoreq.120 Group IV
polyalphaolefins (PAO) Group V All other base oil stocks not
included in Groups I, II, III or IV
[0090] Natural oils include animal oils, vegetable oils (castor oil
and lard oil, for example), and mineral oils. Animal and vegetable
oils possessing favorable thermal oxidative stability can be used.
Of the natural oils, mineral oils are preferred. Mineral oils vary
widely as to their crude source, for example, as to whether they
are paraffinic, naphthenic, or mixed paraffinic-naphthenic. Oils
derived from coal or shale are also useful. Natural oils vary also
as to the method used for their production and purification, for
example, their distillation range and whether they are straight run
or cracked, hydrorefined, or solvent extracted.
[0091] Group II and/or Group III hydroprocessed or hydrocracked
base stocks, including synthetic oils such as alkyl aromatics and
synthetic esters are also well known base stock oils.
[0092] Synthetic oils include hydrocarbon oil. Hydrocarbon oils
include oils such as polymerized and interpolymerized olefins
(polybutylenes, polypropylenes, propylene isobutylene copolymers,
ethylene-olefin copolymers, and ethylene-alphaolefin copolymers,
for example). Polyalphaolefin (PAO) oil base stocks are commonly
used synthetic hydrocarbon oil. By way of example, PAOs derived
from C.sub.8, C.sub.10, C.sub.12, C.sub.14 olefins or mixtures
thereof may be utilized. See U.S. Pat. Nos. 4,956,122; 4,827,064;
and 4,827,073.
[0093] The number average molecular weights of the PAOs, which are
known materials and generally available on a major commercial scale
from suppliers such as ExxonMobil Chemical Company, Chevron
Phillips Chemical Company, BP, and others, typically vary from
about 250 to about 3,000, although PAO's may be made in viscosities
up to about 150 cSt (100.degree. C.). The PAOs are typically
comprised of relatively low molecular weight hydrogenated polymers
or oligomers of alphaolefins which include, but are not limited to,
C.sub.2 to about C.sub.32 alphaolefins with the C.sub.8 to about
C.sub.16 alphaolefins, such as 1-octene, 1-decene, 1-dodecene and
the like, being preferred. The preferred polyalphaolefins are
poly-1-octene, poly-1-decene and poly-1-dodecene and mixtures
thereof and mixed olefin-derived polyolefins. However, the dimers
of higher olefins in the range of C.sub.14 to C.sub.18 may be used
to provide low viscosity base stocks of acceptably low volatility.
Depending on the viscosity grade and the starting oligomer, the
PAOs may be predominantly trimers and tetramers of the starting
olefins, with minor amounts of the higher oligomers, having a
viscosity range of 1.5 to 12 cSt. PAO fluids of particular use may
include 3.0 cSt, 3.4 cSt, and/or 3.6 cSt and combinations thereof.
Mixtures of PAO fluids having a viscosity range of 1.5 to
approximately 150 cSt or more may be used if desired.
[0094] The PAO fluids may be conveniently made by the
polymerization of an alphaolefin in the presence of a
polymerization catalyst such as the Friedel-Crafts catalysts
including, for example, aluminum trichloride, boron trifluoride or
complexes of boron trifluoride with water, alcohols such as
ethanol, propanol or butanol, carboxylic acids or esters such as
ethyl acetate or ethyl propionate. For example the methods
disclosed by U.S. Pat. Nos. 4,149,178 or 3,382,291 may be
conveniently used herein. Other descriptions of PAO synthesis are
found in the following U.S. Pat. Nos. 3,742,082; 3,769,363;
3,876,720; 4,239,930; 4,367,352; 4,413,156; 4,434,408; 4,910,355;
4,956,122; and 5,068,487. The dimers of the C14 to C18 olefins are
described in U.S. Pat. No. 4,218,330.
[0095] Other useful lubricant oil base stocks include wax isomerate
base stocks and base oils, comprising hydroisomerized waxy stocks
(e.g. waxy stocks such as gas oils, slack waxes, fuels hydrocracker
bottoms, etc.), hydroisomerized Fischer-Tropsch waxes,
Gas-to-Liquids (GTL) base stocks and base oils, and other wax
isomerate hydroisomerized base stocks and base oils, or mixtures
thereof. Fischer-Tropsch waxes, the high boiling point residues of
Fischer-Tropsch synthesis, are highly paraffinic hydrocarbons with
very low sulfur content. The hydroprocessing used for the
production of such base stocks may use an amorphous
hydrocracking/hydroisomerization catalyst, such as one of the
specialized lube hydrocracking (LHDC) catalysts or a crystalline
hydrocracking/hydroisomerization catalyst, preferably a zeolitic
catalyst. For example, one useful catalyst is ZSM-48 as described
in U.S. Pat. No. 5,075,269, the disclosure of which is incorporated
herein by reference in its entirety. Processes for making
hydrocracked/hydroisomerized distillates and
hydrocracked/hydroisomerized waxes are described, for example, in
U.S. Pat. Nos. 2,817,693; 4,975,177; 4,921,594 and 4,897,178 as
well as in British Patent Nos. 1,429,494; 1,350,257; 1,440,230 and
1,390,359. Each of the aforementioned patents is incorporated
herein in their entirety. Particularly favorable processes are
described in European Patent Application Nos. 464546 and 464547,
also incorporated herein by reference. Processes using
Fischer-Tropsch wax feeds are described in U.S. Pat. Nos. 4,594,172
and 4,943,672, the disclosures of which are incorporated herein by
reference in their entirety.
[0096] Gas-to-Liquids (GTL) base oils, Fischer-Tropsch wax derived
base oils, and other wax-derived hydroisomerized (wax isomerate)
base oils be advantageously used in the instant disclosure, and may
have useful kinematic viscosities at 100.degree. C. of about 3 cSt
to about 50 cSt, preferably about 3 cSt to about 30 cSt, more
preferably about 3.5 cSt to about 25 cSt, as exemplified by GTL 4
with kinematic viscosity of about 4.0 cSt at 100.degree. C. and a
viscosity index of about 141. These Gas-to-Liquids (GTL) base oils,
Fischer-Tropsch wax derived base oils, and other wax-derived
hydroisomerized base oils may have useful pour points of about
-20.degree. C. or lower, and under some conditions may have
advantageous pour points of about -25.degree. C. or lower, with
useful pour points of about -30.degree. C. to about -40.degree. C.
or lower. Useful compositions of Gas-to-Liquids (GTL) base oils,
Fischer-Tropsch wax derived base oils, and wax-derived
hydroisomerized base oils are recited in U.S. Pat. Nos. 6,080,301;
6,090,989, and 6,165,949 for example, and are incorporated herein
in their entirety by reference.
[0097] The hydrocarbyl aromatics can be used as a base oil or base
oil component and can be any hydrocarbyl molecule that contains at
least about 5% of its weight derived from an aromatic moiety such
as a benzenoid moiety or naphthenoid moiety, or their derivatives.
These hydrocarbyl aromatics include alkyl benzenes, alkyl
naphthalenes, alkyl diphenyl oxides, alkyl naphthols, alkyl
diphenyl sulfides, alkylated bis-phenol A, alkylated thiodiphenol,
and the like. The aromatic can be mono-alkylated, dialkylated,
polyalkylated, and the like. The aromatic can be mono- or
poly-functionalized. The hydrocarbyl groups can also be comprised
of mixtures of alkyl groups, alkenyl groups, alkynyl, cycloalkyl
groups, cycloalkenyl groups and other related hydrocarbyl groups.
The hydrocarbyl groups can range from about C.sub.6 up to about
C.sub.60 with a range of about C.sub.8 to about C.sub.20 often
being preferred. A mixture of hydrocarbyl groups is often
preferred, and up to about three such substituents may be present.
The hydrocarbyl group can optionally contain sulfur, oxygen, and/or
nitrogen containing substituents. The aromatic group can also be
derived from natural (petroleum) sources, provided at least about
5% of the molecule is comprised of an above-type aromatic moiety.
Viscosities at 100.degree. C. of approximately 3 cSt to about 50
cSt are preferred, with viscosities of approximately 3.4 cSt to
about 20 cSt often being more preferred for the hydrocarbyl
aromatic component. In one embodiment, an alkyl naphthalene where
the alkyl group is primarily comprised of 1-hexadecene is used.
Other alkylates of aromatics can be advantageously used.
Naphthalene or methyl naphthalene, for example, can be alkylated
with olefins such as octene, decene, dodecene, tetradecene or
higher, mixtures of similar olefins, and the like. Useful
concentrations of hydrocarbyl aromatic in a lubricant oil
composition can be about 2% to about 25%, preferably about 4% to
about 20%, and more preferably about 4% to about 15%, depending on
the application.
[0098] Alkylated aromatics such as the hydrocarbyl aromatics of the
present disclosure may be produced by well-known Friedel-Crafts
alkylation of aromatic compounds. See Friedel-Crafts and Related
Reactions, Olah, G. A. (ed.), Inter-science Publishers, New York,
1963. For example, an aromatic compound, such as benzene or
naphthalene, is alkylated by an olefin, alkyl halide or alcohol in
the presence of a Friedel-Crafts catalyst. See Friedel-Crafts and
Related Reactions, Vol. 2, part 1, chapters 14, 17, and 18, See
Olah, G. A. (ed.), Inter-science Publishers, New York, 1964. Many
homogeneous or heterogeneous, solid catalysts are known to one
skilled in the art. The choice of catalyst depends on the
reactivity of the starting materials and product quality
requirements. For example, strong acids such as AlCl.sub.3,
BF.sub.3, or HF may be used. In some cases, milder catalysts such
as FeCl.sub.3 or SnCl.sub.4 are preferred. Newer alkylation
technology uses zeolites or solid super acids.
[0099] Esters comprise a useful base stock. Additive solvency and
seal compatibility characteristics may be secured by the use of
esters such as the esters of dibasic acids with monoalkanols and
the polyol esters of monocarboxylic acids. Esters of the former
type include, for example, the esters of dicarboxylic acids such as
phthalic acid, succinic acid, alkyl succinic acid, alkenyl succinic
acid, maleic acid, azelaic acid, suberic acid, sebacic acid,
fumaric acid, adipic acid, linoleic acid dimer, malonic acid, alkyl
malonic acid, alkenyl malonic acid, etc., with a variety of
alcohols such as butyl alcohol, hexyl alcohol, dodecyl alcohol,
2-ethylhexyl alcohol, etc. Specific examples of these types of
esters include dibutyl adipate, di(2-ethylhexyl) sebacate,
di-n-hexyl fumarate, dioctyl sebacate, diisooctyl azelate,
diisodecyl azelate, dioctyl phthalate, didecyl phthalate, dieicosyl
sebacate, etc.
[0100] Particularly useful synthetic esters are those which are
obtained by reacting one or more polyhydric alcohols, preferably
the hindered polyols (such as the neopentyl polyols, e.g.,
neopentyl glycol, trimethylol ethane,
2-methyl-2-propyl-1,3-propanediol, trimethylol propane,
pentaerythritol and dipentaerythritol) with alkanoic acids
containing at least about 4 carbon atoms, preferably C5 to C30
acids such as saturated straight chain fatty acids including
caprylic acid, capric acid, lauric acid, myristic acid, palmitic
acid, stearic acid, arachic acid, and behenic acid, or the
corresponding branched chain fatty acids or unsaturated fatty acids
such as oleic acid, or mixtures of any of these materials.
[0101] Suitable synthetic ester components include the esters of
trimethylol propane, trimethylol butane, trimethylol ethane,
pentaerythritol and/or dipentaerythritol with one or more
monocarboxylic acids containing from about 5 to about 10 carbon
atoms. These esters are widely available commercially, for example,
the Mobil P-41 and P-51 esters of ExxonMobil Chemical Company.
[0102] Also useful are esters derived from renewable material such
as coconut, palm, rapeseed, soy, sunflower and the like. These
esters may be monoesters, di-esters, polyol esters, complex esters,
or mixtures thereof. These esters are widely available
commercially, for example, the Esterex NP 343 ester of ExxonMobil
Chemical Company.
[0103] More particularly, branched polyol esters comprise a useful
base stock of this disclosure. The branched polyol esters are
obtained by reacting one or more polyhydric alcohols, preferably
the hindered polyols (such as the neopentyl polyols, e.g.,
neopentyl glycol, trimethylol ethane,
2-methyl-2-propyl-1,3-propanediol, trimethylol propane,
pentaerythritol and dipentaerythritol) with single or mixed
branched mono-carboxylic acids containing at least about 4 carbon
atoms, preferably C.sub.5 to C.sub.30 branched mono-carboxylic
acids including 2,2-dimethyl propionic acid (neopentanoic acid),
neoheptanoic acid, neooctanoic acid, neononanoic acid, iso-hexanoic
acid, neodecanoic acid, 2-ethyl hexanoic acid (2EH),
3,5,5-trimethyl hexanoic acid (TMH), isoheptanoic acid, isooctanoic
acid, isononanoic acid, isodecanoic acid, or mixtures of any of
these materials. These branched polyol esters include fully
converted and partially converted polyol esters.
[0104] Particularly useful polyols include, for example, neopentyl
glycol, 2,2-dimethylol butane, trimethylol ethane, trimethylol
propane, trimethylol butane, mono-pentaerythritol, technical grade
pentaerythritol, di-pentaerythritol, tri-pentaerythritol, ethylene
glycol, propylene glycol and polyalkylene glycols (e.g.,
polyethylene glycols, polypropylene glycols, 1,4-butanediol,
sorbitol and the like, 2-methylpropanediol, polybutylene glycols,
etc., and blends thereof such as a polymerized mixture of ethylene
glycol and propylene glycol). The most preferred alcohols are
technical grade (e.g., approximately 88% mono-, 10% di- and 1-2%
tri-pentaerythritol) pentaerythritol, mono-pentaerythritol,
di-pentaerythritol, neopentyl glycol and trimethylol propane.
[0105] Particularly useful branched mono-carboxylic acids include,
for example, 2,2-dimethyl propionic acid (neopentanoic acid),
neoheptanoic acid, neooctanoic acid, neononanoic acid, iso-hexanoic
acid, neodecanoic acid, 2-ethyl hexanoic acid (2EH),
3,5,5-trimethyl hexanoic acid (TMH), isoheptanoic acid, isooctanoic
acid, isononanoic acid, isodecanoic acid, or mixtures of any of
these materials. One especially preferred branched acid is
3,5,5-trimethyl hexanoic acid. The term "neo" as used herein refers
to a trialkyl acetic acid, i.e., an acid which is triply
substituted at the alpha carbon with alkyl groups.
[0106] Preferably, the branched polyol ester is derived from a
polyhydric alcohol and a branched mono-carboxylic acid. In
particular, the branched polyol ester is obtained by reacting one
or more polyhydric alcohols with one or more branched
mono-carboxylic acids containing at least about 4 carbon atoms.
[0107] Preferred branched polyol esters useful in this disclosure
include, for example, mono-pentaerythritol ester of branched
mono-carboxylic acids, di-pentaerythritol ester of branched
mono-carboxylic acids, trimethylolpropane ester of C8-C10 acids,
and the like.
[0108] Other synthetic esters that can be useful in this disclosure
are those which are obtained by reacting one or more polyhydric
alcohols, preferably the hindered polyols (such as the neopentyl
polyols, e.g., neopentyl glycol, trimethylol ethane,
2-methyl-2-propyl-1,3-propanediol, trimethylol propane,
pentaerythritol and dipentaerythritol) with mono carboxylic acids
containing at least about 4 carbon atoms, preferably branched
C.sub.5 to C.sub.30 acids including caprylic acid, capric acid,
lauric acid, myristic acid, palmitic acid, stearic acid, arachic
acid, and behenic acid, or the corresponding branched chain fatty
acids or unsaturated fatty acids such as oleic acid, or mixtures of
any of these materials.
[0109] Other ester base oils useful in this disclosure include
adipate esters. The dialkyl adipate ester is derived from adipic
acid and a branched alkyl alcohol.
[0110] Mixtures of branched polyol ester base stocks with other
lubricating oil base stocks (e.g., Groups I, II, III, IV and V base
stocks) may be useful in the lubricating oil formulations of this
disclosure.
[0111] The branched polyol ester can be present in an amount of
from about 1 to about 50 weight percent, or from about 5 to about
45 weight percent, or from about 10 to about 40 weight percent, or
from about 15 to about 35 weight percent, or from about 20 to about
30 weight percent, based on the total weight of the formulated
oil.
[0112] Engine oil formulations containing renewable esters are
included in this disclosure. For such formulations, the renewable
content of the ester is typically greater than about 70 weight
percent, preferably more than about 80 weight percent and most
preferably more than about 90 weight percent.
[0113] Other useful fluids of lubricating viscosity include
non-conventional or unconventional base stocks that have been
processed, preferably catalytically, or synthesized to provide high
performance lubrication characteristics.
[0114] Non-conventional or unconventional base stocks/base oils
include one or more of a mixture of base stock(s) derived from one
or more Gas-to-Liquids (GTL) materials, as well as
isomerate/isodewaxate base stock(s) derived from natural wax or
waxy feeds, mineral and or non-mineral oil waxy feed stocks such as
slack waxes, natural waxes, and waxy stocks such as gas oils, waxy
fuels hydrocracker bottoms, waxy raffinate, hydrocrackate, thermal
crackates, or other mineral, mineral oil, or even non-petroleum oil
derived waxy materials such as waxy materials received from coal
liquefaction or shale oil, and mixtures of such base stocks.
[0115] GTL materials are materials that are derived via one or more
synthesis, combination, transformation, rearrangement, and/or
degradation/deconstructive processes from gaseous carbon-containing
compounds, hydrogen-containing compounds and/or elements as feed
stocks such as hydrogen, carbon dioxide, carbon monoxide, water,
methane, ethane, ethylene, acetylene, propane, propylene, propyne,
butane, butylenes, and butynes. GTL base stocks and/or base oils
are GTL materials of lubricating viscosity that are generally
derived from hydrocarbons; for example, waxy synthesized
hydrocarbons, that are themselves derived from simpler gaseous
carbon-containing compounds, hydrogen-containing compounds and/or
elements as feed stocks. GTL base stock(s) and/or base oil(s)
include oils boiling in the lube oil boiling range (1)
separated/fractionated from synthesized GTL materials such as, for
example, by distillation and subsequently subjected to a final wax
processing step which involves either or both of a catalytic
dewaxing process, or a solvent dewaxing process, to produce lube
oils of reduced/low pour point; (2) synthesized wax isomerates,
comprising, for example, hydrodewaxed or hydroisomerized cat and/or
solvent dewaxed synthesized wax or waxy hydrocarbons; (3)
hydrodewaxed or hydroisomerized cat and/or solvent dewaxed
Fischer-Tropsch (F-T) material (i.e., hydrocarbons, waxy
hydrocarbons, waxes and possible analogous oxygenates); preferably
hydrodewaxed or hydroisomerized/followed by cat and/or solvent
dewaxing dewaxed F-T waxy hydrocarbons, or hydrodewaxed or
hydroisomerized/followed by cat (or solvent) dewaxing dewaxed, F-T
waxes, or mixtures thereof.
[0116] GTL base stock(s) and/or base oil(s) derived from GTL
materials, especially, hydrodewaxed or hydroisomerized/followed by
cat and/or solvent dewaxed wax or waxy feed, preferably F-T
material derived base stock(s) and/or base oil(s), are
characterized typically as having kinematic viscosities at
100.degree. C. of from about 2 mm.sup.2/s to about 50 mm.sup.2/s
(ASTM D445). They are further characterized typically as having
pour points of -5.degree. C. to about -40.degree. C. or lower (ASTM
D97). They are also characterized typically as having viscosity
indices of about 80 to about 140 or greater (ASTM D2270).
[0117] In addition, the GTL base stock(s) and/or base oil(s) are
typically highly paraffinic (>90% saturates), and may contain
mixtures of monocycloparaffins and multicycloparaffins in
combination with non-cyclic isoparaffins. The ratio of the
naphthenic (i.e., cycloparaffin) content in such combinations
varies with the catalyst and temperature used. Further, GTL base
stock(s) and/or base oil(s) typically have very low sulfur and
nitrogen content, generally containing less than about 10 ppm, and
more typically less than about 5 ppm of each of these elements. The
sulfur and nitrogen content of GTL base stock(s) and/or base oil(s)
obtained from F-T material, especially F-T wax, is essentially nil.
In addition, the absence of phosphorus and aromatics make this
materially especially suitable for the formulation of low SAP
products.
[0118] The term GTL base stock and/or base oil and/or wax isomerate
base stock and/or base oil is to be understood as embracing
individual fractions of such materials of wide viscosity range as
recovered in the production process, mixtures of two or more of
such fractions, as well as mixtures of one or two or more low
viscosity fractions with one, two or more higher viscosity
fractions to produce a blend wherein the blend exhibits a target
kinematic viscosity.
[0119] The GTL material, from which the GTL base stock(s) and/or
base oil(s) is/are derived is preferably an F-T material (i.e.,
hydrocarbons, waxy hydrocarbons, wax).
[0120] Base oils for use in the formulated lubricating oils useful
in the present disclosure are any of the variety of oils
corresponding to API Group I, Group II, Group III, Group IV, and
Group V oils and mixtures thereof, preferably API Group II, Group
III, Group IV, and Group V oils and mixtures thereof, more
preferably the Group III to Group V base oils due to their
exceptional volatility, stability, viscometric and cleanliness
features. Minor quantities of Group I stock, such as the amount
used to dilute additives for blending into formulated lube oil
products, can be tolerated but should be kept to a minimum, i.e.
amounts only associated with their use as diluent/carrier oil for
additives used on an "as-received" basis. Even in regard to the
Group II stocks, it is preferred that the Group II stock be in the
higher quality range associated with that stock, i.e. a Group II
stock having a viscosity index in the range 100<VI<120.
Groups II and III base stocks can be included in the lubricating
oil formulations of this disclosure, but preferably only those with
high quality, e.g., those having a VI from 100 to 120. Group IV and
V base stocks, preferably those of high quality, are desirably
included into the lubricating oil formulations of this
disclosure.
[0121] The base oil or base stock constitutes the major component
or major amount of the lubricating oil compositions of the present
disclosure and typically is present in an amount ranging from about
5 to about 99 weight percent, or about 7 to about 95 weight
percent, or about 10 to about 90 weight percent, or about 20 to
about 80 weight percent, preferably from about 70 to about 95
weight percent, and more preferably from about 85 to about 95
weight percent, based on the total weight of the composition. The
base oil or base stock may be selected from any of the synthetic or
natural oils typically used as crankcase lubricating oils for
spark-ignited and compression-ignited engines.
[0122] The base oil or base stock conveniently has a kinematic
viscosity, according to ASTM standards, of about 2.5 cSt to about
12 cSt (or mm.sup.2/s) at 100.degree. C. and preferably of about
2.5 cSt to about 9 cSt (or mm.sup.2/s) at 100.degree. C.
[0123] Mixtures of synthetic and natural base oils may be used if
desired. Bi-modal mixtures of Group I, II, III, IV, and/or V base
stocks may be used if desired. A second base stock or co-base stock
may be also optionally incorporated into the lubricating oil
compositions of this disclosure in an amount ranging from about 5
to about 80 weight percent, or about 10 to about 60 weight percent,
or about 15 to about 50 weight percent, or about 20 to about 40
weight percent, or from about 25 to about 35 weight percent.
Other Lubricating Oil Additives of the Lubricating Oil Compositions
of this Disclosure
[0124] The lubricating oil compositions (preferably lubricating oil
formulations) of this disclosure may additionally contain one or
more of the commonly used other lubricating oil performance
additives including but not limited to dispersants, viscosity
modifiers, antiwear additives, corrosion inhibitors, rust
inhibitors, metal deactivators, extreme pressure additives,
anti-seizure agents, wax modifiers, fluid-loss additives, seal
compatibility agents, lubricity agents, anti-staining agents,
chromophoric agents, defoamants, demulsifiers, densifiers, wetting
agents, gelling agents, tackiness agents, colorants, and others.
For a review of many commonly used additives and the quantities
used, see: (i) Klamann in Lubricants and Related Products, Verlag
Chemie, Deerfield Beach, Fla.; ISBN 0-89573-177-0; (ii) "Lubricant
Additives," M. W. Ranney, published by Noyes Data Corporation of
Parkridge, N J (1973); (iii) "Synthetics, Mineral Oils, and
Bio-Based Lubricants," Edited by L. R. Rudnick, CRC Taylor and
Francis, 2006, ISBN 1-57444-723-8; (iv) "Lubrication Fundamentals",
J. G. Wills, Marcel Dekker Inc., (New York, 1980); (v) Synthetic
Lubricants and High-Performance Functional Fluids, 2nd Ed., Rudnick
and Shubkin, Marcel Dekker Inc., (New York, 1999); and (vi)
"Polyalphaolefins," L. R. Rudnick, Chemical Industries (Boca Raton,
Fla., United States) (2006), 111 (Synthetics, Mineral Oils, and
Bio-Based Lubricants), 3-36. Reference is also made to: (a) U.S.
Pat. No. 7,704,930 B2; (b) U.S. Pat. No. 9,458,403 B2, Column 18,
line 46 to Column 39, line 68; (c) U.S. Pat. No. 9,422,497 B2,
Column 34, line 4 to Column 40, line 55; and (d) U.S. Pat. No.
8,048,833 B2, Column 17, line 48 to Column 27, line 12, the
disclosures of which are incorporated herein in its entirety. These
additives are commonly delivered with varying amounts of diluent
oil that may range from 5 wt % to 50 wt % based on the total weight
of the additive package before incorporation into the formulated
oil.
[0125] Further details of the other lubricating oil additives
useful in the lubricating oil compositions of this disclosure are
as follows:
Viscosity Modifiers
[0126] Viscosity modifiers provide lubricants with high and low
temperature operability. These additives impart shear stability at
elevated temperatures and acceptable viscosity at low
temperatures.
[0127] Non-limiting exemplary viscosity modifiers for the inventive
lubricating oils are as follows: high molecular weight
hydrocarbons, polyesters and viscosity modifier dispersants that
function as both a viscosity modifier and a dispersant. Typical
molecular weights of these polymers are between about 10,000 to
1,500,000, more typically about 20,000 to 1,200,000, and even more
typically between about 50,000 and 1,000,000.
[0128] Other examples of suitable viscosity modifiers are linear or
star-shaped polymers and copolymers of methacrylate, butadiene,
olefins, or alkylated styrenes. Polyisobutylene is a commonly used
viscosity modifier. Another suitable viscosity modifier is
polymethacrylate (copolymers of various chain length alkyl
methacrylates, for example), some formulations of which also serve
as pour point depressants. Other suitable viscosity modifiers
include copolymers of ethylene and propylene, hydrogenated block
copolymers of styrene and isoprene, and polyacrylates (copolymers
of various chain length acrylates, for example). Specific examples
include styrene-isoprene or styrene-butadiene based polymers of
50,000 to 200,000 molecular weight.
[0129] Olefin copolymers are commercially available from Chevron
Oronite Company LLC under the trade designation "PARATONE.RTM."
(such as "PARATONE.RTM. 8921" and "PARATONE.RTM. 8941"); from Afton
Chemical Corporation under the trade designation "HiTEC.RTM." (such
as "HiTEC.RTM. 5850B"; and from The Lubrizol Corporation under the
trade designation "Lubrizol.RTM. 7067C". Hydrogenated polyisoprene
star polymers are commercially available from Infineum
International Limited, e.g., under the trade designation "SV200"
and "SV600". Hydrogenated diene-styrene block copolymers are
commercially available from Infineum International Limited, e.g.,
under the trade designation "SV 50".
[0130] The polymethacrylate or polyacrylate polymers can be linear
polymers which are available from Evonik Industries under the trade
designation "Viscoplex.RTM." (e.g., Viscoplex 6-954) or star
polymers which are available from Lubrizol Corporation under the
trade designation Asteric.TM. (e.g., Lubrizol 87708 and Lubrizol
87725).
[0131] Illustrative vinyl aromatic-containing polymers as viscosity
modifiers useful in this disclosure may be derived predominantly
from vinyl aromatic hydrocarbon monomer. Illustrative vinyl
aromatic-containing copolymers useful in this disclosure may be
represented by the following general formula:
A-B
wherein A is a polymeric block derived predominantly from vinyl
aromatic hydrocarbon monomer, and B is a polymeric block derived
predominantly from conjugated diene monomer.
[0132] In another embodiment of this disclosure, the at least one
viscosity modifier may be used in an amount of less than about 20
weight percent, or less than about 15 weight percent, or less than
about 10 weight percent, or less than about 7 weight percent, or
less than about 5 weight percent, and in certain instances, may be
used at less than 2 weight percent, or less than about 1 weight
percent, or less than about 0.5 weight percent, based on the total
weight of the formulated oil or lubricating engine oil. The
preferred range for the at least one viscosity modifier is from 5
to 20 wt % of the formulated oil.
[0133] Viscosity modifiers are typically added as concentrates, in
large amounts of diluent oil. As used herein, the viscosity
modifier concentrations are given on an "as delivered" basis.
Typically, the active polymer is delivered with a diluent oil. The
"as delivered" viscosity modifier typically contains from 20 weight
percent to 75 weight percent of an active polymer for
polymethacrylate or polyacrylate polymers, or from 8 weight percent
to 20 weight percent of an active polymer for olefin copolymers,
hydrogenated polyisoprene star polymers, or hydrogenated
diene-styrene block copolymers, in the "as delivered" polymer
concentrate.
Antiwear Additives
[0134] A metal alkylthiophosphate and more particularly a metal
dialkyl dithio phosphate in which the metal constituent is zinc, or
zinc dialkyl dithio phosphate (ZDDP) can be a useful component of
the lubricating oils of this disclosure. ZDDP can be derived from
primary alcohols, secondary alcohols or mixtures thereof. ZDDP
compounds generally are of the formula
Zn[SP(S)(OR.sup.1)(OR.sup.2)].sub.2
where R.sup.1 and R.sup.2 are C.sub.1-C.sub.18 alkyl groups,
preferably C.sub.2-C.sub.12 alkyl groups. These alkyl groups may be
straight chain or branched. Alcohols used in the ZDDP can be
2-propanol, butanol, secondary butanol, pentanols, hexanols such as
4-methyl-2-pentanol, n-hexanol, n-octanol, 2-ethyl hexanol,
alkylated phenols, and the like. Mixtures of secondary alcohols or
of primary and secondary alcohol can be preferred. Alkyl aryl
groups may also be used.
[0135] Preferable zinc dithiophosphates which are commercially
available include secondary zinc dithiophosphates such as those
available from for example, The Lubrizol Corporation under the
trade designations "LZ 677A", "LZ 1095" and "LZ 1371", from for
example Chevron Oronite under the trade designation "OLOA 262" and
from for example Afton Chemical under the trade designation "HITEC
7169".
[0136] The ZDDP is typically used in amounts of from about 0.4
weight percent to about 1.2 weight percent, preferably from about
0.5 weight percent to about 1.0 weight percent, and more preferably
from about 0.6 weight percent to about 0.8 weight percent, based on
the total weight of the lubricating oil, although more or less can
often be used advantageously. Preferably, the ZDDP is a secondary
ZDDP and present in an amount of from about 0.6 to 1.0 weight
percent of the total weight of the lubricating oil.
[0137] Low phosphorus engine oil formulations are included in this
disclosure. For such formulations, the phosphorus content is
typically less than about 0.12 weight percent preferably less than
about 0.10 weight percent and most preferably less than about 0.085
weight percent.
Dispersants
[0138] During engine operation, oil-insoluble oxidation byproducts
are produced. Dispersants help keep these byproducts in solution,
thus diminishing their deposition on metal surfaces. Dispersants
used in the formulation of the lubricating oil may be ashless or
ash-forming in nature. Preferably, the dispersant is ashless. So
called ashless dispersants are organic materials that form
substantially no ash upon combustion. For example,
non-metal-containing or borated metal-free dispersants are
considered ashless. In contrast, metal-containing detergents
discussed herein form ash upon combustion.
[0139] Suitable dispersants typically contain a polar group
attached to a relatively high molecular weight hydrocarbon chain.
The polar group typically contains at least one element of
nitrogen, oxygen, or phosphorus. Typical hydrocarbon chains contain
50 to 400 carbon atoms.
[0140] A particularly useful class of dispersants are the
(poly)alkenylsuccinic derivatives, typically produced by the
reaction of a long chain hydrocarbyl substituted succinic compound,
usually a hydrocarbyl substituted succinic anhydride, with a
polyhydroxy or polyamino compound. The long chain hydrocarbyl group
constituting the oleophilic portion of the molecule which confers
solubility in the oil, is normally a polyisobutylene group. Many
examples of this type of dispersant are well known commercially and
in the literature. Exemplary U.S. patents describing such
dispersants are U.S. Pat. Nos. 3,172,892; 3,215,707; 3,219,666;
3,316,177; 3,341,542; 3,444,170; 3,454,607; 3,541,012; 3,630,904;
3,632,511; 3,787,374 and 4,234,435. Other types of dispersant are
described in U.S. Pat. Nos. 3,036,003; 3,200,107; 3,254,025;
3,275,554; 3,438,757; 3,454,555; 3,565,804; 3,413,347; 3,697,574;
3,725,277; 3,725,480; 3,726,882; 4,454,059; 3,329,658; 3,449,250;
3,519,565; 3,666,730; 3,687,849; 3,702,300; 4,100,082; 5,705,458. A
further description of dispersants may be found, for example, in
European Patent Application No. 471 071, to which reference is made
for this purpose.
[0141] Hydrocarbyl-substituted succinic acid and
hydrocarbyl-substituted succinic anhydride derivatives are useful
dispersants. In particular, succinimide, succinate esters, or
succinate ester amides prepared by the reaction of a
hydrocarbon-substituted succinic acid compound preferably having at
least 50 carbon atoms in the hydrocarbon substituent, with at least
one equivalent of an alkylene amine are particularly useful.
[0142] Succinimides are formed by the condensation reaction between
hydrocarbyl substituted succinic anhydrides and amines. Molar
ratios can vary depending on the polyamine. For example, the molar
ratio of hydrocarbyl substituted succinic anhydride to TEPA can
vary from about 1:1 to about 5:1. Representative examples are shown
in U.S. Pat. Nos. 3,087,936; 3,172,892; 3,219,666; 3,272,746;
3,322,670; and 3,652,616, 3,948,800; and Canada Patent No.
1,094,044.
[0143] Succinate esters are formed by the condensation reaction
between hydrocarbyl substituted succinic anhydrides and alcohols or
polyols. Molar ratios can vary depending on the alcohol or polyol
used. For example, the condensation product of a hydrocarbyl
substituted succinic anhydride and pentaerythritol is a useful
dispersant.
[0144] Succinate ester amides are formed by condensation reaction
between hydrocarbyl substituted succinic anhydrides and alkanol
amines. For example, suitable alkanol amines include ethoxylated
polyalkylpolyamines, propoxylated polyalkylpolyamines and
polyalkenylpolyamines such as polyethylene polyamines. One example
is propoxylated hexamethylenediamine. Representative examples are
shown in U.S. Pat. No. 4,426,305.
[0145] The molecular weight of the hydrocarbyl substituted succinic
anhydrides used in the preceding paragraphs will typically range
between 800 and 2,500 or more. The above products can be
post-reacted with various reagents such as sulfur, oxygen,
formaldehyde, carboxylic acids such as oleic acid. The above
products can also be post reacted with boron compounds such as
boric acid, borate esters or highly borated dispersants, to form
borated dispersants generally having from about 0.1 to about 5
moles of boron per mole of dispersant reaction product.
[0146] Mannich base dispersants are made from the reaction of
alkylphenols, formaldehyde, and amines. See U.S. Pat. No.
4,767,551, which is incorporated herein by reference. Process aids
and catalysts, such as oleic acid and sulfonic acids, can also be
part of the reaction mixture. Molecular weights of the alkylphenols
range from 800 to 2,500. Representative examples are shown in U.S.
Pat. Nos. 3,697,574; 3,703,536; 3,704,308; 3,751,365; 3,756,953;
3,798,165; and 3,803,039.
[0147] Typical high molecular weight aliphatic acid modified
Mannich condensation products useful in this disclosure can be
prepared from high molecular weight alkyl-substituted
hydroxyaromatics or HNR.sub.2 group-containing reactants.
[0148] Hydrocarbyl substituted amine ashless dispersant additives
are well known to one skilled in the art; see, for example, U.S.
Pat. Nos. 3,275,554; 3,438,757; 3,565,804; 3,755,433, 3,822,209,
and 5,084,197.
[0149] Preferred dispersants include borated and non-borated
succinimides, including those derivatives from mono-succinimides,
bis-succinimides, and/or mixtures of mono- and bis-succinimides,
wherein the hydrocarbyl succinimide is derived from a
hydrocarbylene group such as polyisobutylene having a Mn of from
about 500 to about 5000, or from about 1000 to about 3000, or about
1000 to about 2000, or a mixture of such hydrocarbylene groups,
often with high terminal vinylic groups. Other preferred
dispersants include succinic acid-esters and amides,
alkylphenol-polyamine-coupled Mannich adducts, their capped
derivatives, and other related components.
[0150] Polymethacrylate or polyacrylate derivatives are another
class of dispersants. These dispersants are typically prepared by
reacting a nitrogen containing monomer and a methacrylic or acrylic
acid esters containing 5-25 carbon atoms in the ester group.
Representative examples are shown in U.S. Pat. Nos. 2,100,993, and
6,323,164. Polymethacrylate and polyacrylate dispersants are
normally used as multifunctional viscosity modifiers. The lower
molecular weight versions can be used as lubricant dispersants or
fuel detergents.
[0151] Illustrative preferred dispersants useful in this disclosure
include those derived from polyalkenyl-substituted mono- or
dicarboxylic acid, anhydride or ester, which dispersant has a
polyalkenyl moiety with a number average molecular weight of at
least 900 and from greater than 1.3 to 1.7, preferably from greater
than 1.3 to 1.6, most preferably from greater than 1.3 to 1.5,
functional groups (mono- or dicarboxylic acid producing moieties)
per polyalkenyl moiety (a medium functionality dispersant).
Functionality (F) can be determined according to the following
formula:
F=(SAP.times.M.sub.n)/((112,200.times.A.I.)-(SAP.times.98))
wherein SAP is the saponification number (i.e., the number of
milligrams of KOH consumed in the complete neutralization of the
acid groups in one gram of the succinic-containing reaction
product, as determined according to ASTM D94); M.sub.n is the
number average molecular weight of the starting olefin polymer; and
A.I. is the percent active ingredient of the succinic-containing
reaction product (the remainder being unreacted olefin polymer,
succinic anhydride and diluent).
[0152] The polyalkenyl moiety of the dispersant may have a number
average molecular weight of at least 900, suitably at least 1500,
preferably between 1800 and 3000, such as between 2000 and 2800,
more preferably from about 2100 to 2500, and most preferably from
about 2200 to about 2400. The molecular weight of a dispersant is
generally expressed in terms of the molecular weight of the
polyalkenyl moiety. This is because the precise molecular weight
range of the dispersant depends on numerous parameters including
the type of polymer used to derive the dispersant, the number of
functional groups, and the type of nucleophilic group employed.
[0153] Polymer molecular weight, specifically M.sub.n, can be
determined by various known techniques. One convenient method is
gel permeation chromatography (GPC), which additionally provides
molecular weight distribution information (see W. W. Yau, J. J.
Kirkland and D. D. Bly, "Modern Size Exclusion Liquid
Chromatography", John Wiley and Sons, New York, 1979). Another
useful method for determining molecular weight, particularly for
lower molecular weight polymers, is vapor pressure osmometry (e.g.,
ASTM D3592).
[0154] The polyalkenyl moiety in a dispersant preferably has a
narrow molecular weight distribution (MWD), also referred to as
polydispersity, as determined by the ratio of weight average
molecular weight (M.sub.w) to number average molecular weight
(M.sub.n). Polymers having a M.sub.w/M.sub.n of less than 2.2,
preferably less than 2.0, are most desirable. Suitable polymers
have a polydispersity of from about 1.5 to 2.1, preferably from
about 1.6 to about 1.8.
[0155] Suitable polyalkenes employed in the formation of the
dispersants include homopolymers, interpolymers or lower molecular
weight hydrocarbons. One family of such polymers comprise polymers
of ethylene and/or at least one C.sub.3 to C.sub.2 alpha-olefin
having the formula H.sub.2C.dbd.CHR.sup.1 wherein R.sup.1 is a
straight or branched chain alkyl radical comprising 1 to 26 carbon
atoms and wherein the polymer contains carbon-to-carbon
unsaturation, and a high degree of terminal ethenylidene
unsaturation. Preferably, such polymers comprise interpolymers of
ethylene and at least one alpha-olefin of the above formula,
wherein R.sup.1 is alkyl of from 1 to 18 carbon atoms, and more
preferably is alkyl of from 1 to 8 carbon atoms, and more
preferably still of from 1 to 2 carbon atoms.
[0156] Another useful class of polymers is polymers prepared by
cationic polymerization of monomers such as isobutene and styrene.
Common polymers from this class include polyisobutenes obtained by
polymerization of a C.sub.4 refinery stream having a butene content
of 35 to 75% by wt., and an isobutene content of 30 to 60% by wt. A
preferred source of monomer for making poly-n-butenes is petroleum
feedstreams such as Raffinate II. These feedstocks are disclosed in
the art such as in U.S. Pat. No. 4,952,739. A preferred embodiment
utilizes polyisobutylene prepared from a pure isobutylene stream or
a Raffinate I stream to prepare reactive isobutylene polymers with
terminal vinylidene olefins. Polyisobutene polymers that may be
employed are generally based on a polymer chain of from 1500 to
3000.
[0157] The dispersant(s) are preferably non-polymeric (e.g., mono-
or bis-succinimides). Such dispersants can be prepared by
conventional processes such as disclosed in U.S. Patent Application
Publication No. 2008/0020950, the disclosure of which is
incorporated herein by reference.
[0158] The dispersant(s) can be borated by conventional means, as
generally disclosed in U.S. Pat. Nos. 3,087,936, 3,254,025 and
5,430,105.
[0159] Such dispersants may be used in an amount of about 0.01 to
20 weight percent or 0.01 to 10 weight percent, preferably about
0.5 to 8 weight percent, or more preferably 0.5 to 4 weight
percent. Or such dispersants may be used in an amount of about 2 to
12 weight percent, preferably about 4 to 10 weight percent, or more
preferably 6 to 9 weight percent. On an active ingredient basis,
such additives may be used in an amount of about 0.06 to 14 weight
percent, preferably about 0.3 to 6 weight percent. The hydrocarbon
portion of the dispersant atoms can range from C.sub.60 to
C.sub.1000, or from C.sub.70 to C.sub.300, or from C.sub.70 to
C.sub.200. These dispersants may contain both neutral and basic
nitrogen, and mixtures of both. Dispersants can be end-capped by
borates and/or cyclic carbonates. Nitrogen content in the finished
oil can vary from about 200 ppm by weight to about 2000 ppm by
weight, preferably from about 200 ppm by weight to about 1200 ppm
by weight. Basic nitrogen can vary from about 100 ppm by weight to
about 1000 ppm by weight, preferably from about 100 ppm by weight
to about 600 ppm by weight.
[0160] As used herein, the dispersant concentrations are given on
an "as delivered" basis. Typically, the active dispersant is
delivered with a process oil. The "as delivered" dispersant
typically contains from about 20 weight percent to about 80 weight
percent, or from about 40 weight percent to about 60 weight
percent, of active dispersant in the "as delivered" dispersant
product.
Antioxidants
[0161] Antioxidants retard the oxidative degradation of base oils
during service. Such degradation may result in deposits on metal
surfaces, the presence of sludge, or a viscosity increase in the
lubricant. One skilled in the art knows a wide variety of oxidation
inhibitors that are useful in lubricating oil compositions. See,
Klamann in Lubricants and Related Products, op cite, and U.S. Pat.
Nos. 4,798,684 and 5,084,197, for example.
[0162] Useful antioxidants include hindered phenols. These phenolic
antioxidants may be ashless (metal-free) phenolic compounds or
neutral or basic metal salts of certain phenolic compounds. Typical
phenolic antioxidant compounds are the hindered phenolics which are
the ones which contain a sterically hindered hydroxyl group, and
these include those derivatives of dihydroxy aryl compounds in
which the hydroxyl groups are in the o- or p-position to each
other. Typical phenolic antioxidants include the hindered phenols
substituted with C.sub.6+ alkyl groups and the alkylene coupled
derivatives of these hindered phenols. Examples of phenolic
materials of this type 2-t-butyl-4-heptyl phenol; 2-t-butyl-4-octyl
phenol; 2-t-butyl-4-dodecyl phenol; 2,6-di-t-butyl-4-heptyl phenol;
2,6-di-t-butyl-4-dodecyl phenol; 2-methyl-6-t-butyl-4-heptyl
phenol; and 2-methyl-6-t-butyl-4-dodecyl phenol. Other useful
hindered mono-phenolic antioxidants may include for example
hindered 2,6-di-alkyl-phenolic proprionic ester derivatives.
Bis-phenolic antioxidants may also be advantageously used in
combination with the instant disclosure. Examples of ortho-coupled
phenols include: 2,2'-bis(4-heptyl-6-t-butyl-phenol);
2,2'-bis(4-octyl-6-t-butyl-phenol); and
2,2'-bis(4-dodecyl-6-t-butyl-phenol). Para-coupled bisphenols
include for example 4,4'-bis(2,6-di-t-butyl phenol) and
4,4'-methylene-bis(2,6-di-t-butyl phenol).
[0163] Effective amounts of one or more catalytic antioxidants may
also be used. The catalytic antioxidants comprise an effective
amount of a) one or more oil soluble polymetal organic compounds;
and, effective amounts of b) one or more substituted
N,N'-diaryl-o-phenylenediamine compounds or c) one or more hindered
phenol compounds; or a combination of both b) and c). Catalytic
antioxidants are more fully described in U.S. Pat. No. 8,048,833,
herein incorporated by reference in its entirety.
[0164] Non-phenolic oxidation inhibitors which may be used include
aromatic amine antioxidants and these may be used either as such or
in combination with phenolics. Typical examples of non-phenolic
antioxidants include: alkylated and non-alkylated aromatic amines
such as aromatic monoamines of the formula R.sup.8R.sup.9R.sup.10N
where R.sup.8 is an aliphatic, aromatic or substituted aromatic
group, R.sup.9 is an aromatic or a substituted aromatic group, and
R.sup.10 is H, alkyl, aryl or R.sup.11S(O).sub.XR.sup.12 where
R.sup.11 is an alkylene, alkenylene, or aralkylene group, R.sup.12
is a higher alkyl group, or an alkenyl, aryl, or alkaryl group, and
x is 0, 1 or 2. The aliphatic group R.sup.8 may contain from 1 to
about 20 carbon atoms, and preferably contains from about 6 to 12
carbon atoms. The aliphatic group is a saturated aliphatic group.
Preferably, both R.sup.8 and R.sup.9 are aromatic or substituted
aromatic to groups, and the aromatic group may be a fused ring
aromatic group such as naphthyl. Aromatic groups R.sup.8 and
R.sup.9 may be joined together with other groups such as S.
[0165] Typical aromatic amines antioxidants have alkyl substituent
groups of at least about 6 carbon atoms. Examples of aliphatic
groups include hexyl, heptyl, octyl, nonyl, and decyl. Generally,
the aliphatic groups will not contain more than about 14 carbon
atoms. The general types of amine antioxidants useful in the
present compositions include diphenylamines, phenyl naphthylamines,
phenothiazines, imidodibenzyls and diphenyl phenylene diamines.
Mixtures of two or more aromatic amines are also useful. Polymeric
amine antioxidants can also be used. Particular examples of
aromatic amine antioxidants useful in the present disclosure
include: p,p'-dioctyldiphenylamine;
t-octylphenyl-alpha-naphthylamine; phenyl-alphanaphthylamine; and
p-octylphenyl-alpha-naphthylamine.
[0166] Sulfurized alkyl phenols and alkali or alkaline earth metal
salts thereof also are useful antioxidants.
[0167] Preferred antioxidants include hindered phenols, arylamines.
These antioxidants may be used individually by type or in
combination with one another. Such additives may be used in an
amount of about 0.01 to 5 weight percent, preferably about 0.01 to
1.5 weight percent, more preferably zero to less than 1.5 weight
percent, more preferably zero to less than 1 weight percent.
Pour Point Depressants (PPDs)
[0168] Conventional pour point depressants (also known as lube oil
flow improvers) may be added to the compositions of the present
disclosure if desired. These pour point depressant may be added to
lubricating compositions of the present disclosure to lower the
minimum temperature at which the fluid will flow or can be poured.
Examples of suitable pour point depressants include
polymethacrylates, polyacrylates, polyarylamides, condensation
products of haloparaffin waxes and aromatic compounds, vinyl
carboxylate polymers, and terpolymers of dialkylfumarates, vinyl
esters of fatty acids and allyl vinyl ethers. U.S. Pat. Nos.
1,815,022; 2,015,748; 2,191,498; 2,387,501; 2,655, 479; 2,666,746;
2,721,877; 2,721,878; and 3,250,715 describe useful pour point
depressants and/or the preparation thereof. Such additives may be
used in an amount of about 0.01 to 5 weight percent, preferably
about 0.01 to 1.5 weight percent.
Seal Compatibility Agents
[0169] Seal compatibility agents help to swell elastomeric seals by
causing a chemical reaction in the fluid or physical change in the
elastomer. Suitable seal compatibility agents for lubricating oils
include organic phosphates, aromatic esters, aromatic hydrocarbons,
esters (butylbenzyl phthalate, for example), and polybutenyl
succinic anhydride. Such additives may be used in an amount of
about 0.01 to 3 weight percent, preferably about 0.01 to 2 weight
percent.
Antifoam Agents
[0170] Anti-foam agents may advantageously be added to lubricant
compositions. These agents retard the formation of stable foams.
Silicones and organic polymers are typical anti-foam agents. For
example, polysiloxanes, such as silicon oil or polydimethyl
siloxane, provide antifoam properties. Anti-foam agents are
commercially available and may be used in conventional minor
amounts along with other additives such as demulsifiers; usually
the amount of these additives combined is less than 1 weight
percent and often less than 0.1 weight percent.
Inhibitors and Antirust Additives
[0171] Antirust additives (or corrosion inhibitors) are additives
that protect lubricated metal surfaces against chemical attack by
water or other contaminants. A wide variety of these are
commercially available.
[0172] One type of antirust additive is a polar compound that wets
the metal surface preferentially, protecting it with a film of oil.
Another type of antirust additive absorbs water by incorporating it
in a water-in-oil emulsion so that only the oil touches the metal
surface. Yet another type of antirust additive chemically adheres
to the metal to produce a non-reactive surface. Examples of
suitable additives include zinc dithiophosphates, metal phenolates,
basic metal sulfonates, fatty acids and amines. Such additives may
be used in an amount of about 0.01 to 5 weight percent, preferably
about 0.01 to 1.5 weight percent.
[0173] The types and quantities of performance additives used in
combination with the instant disclosure in lubricant compositions
are not limited by the examples shown herein as illustrations.
[0174] When lubricating oil compositions contain one or more of the
additives discussed above, the additive(s) are blended into the
composition in an amount sufficient for it to perform its intended
function. Typical amounts of such additives useful in the present
disclosure are shown in Table 1 below.
[0175] It is noted that many of the additives are shipped from the
additive manufacturer as a concentrate, containing one or more
additives together, with a certain amount of base oil diluents.
Accordingly, the weight amounts in the table below, as well as
other amounts mentioned herein, are directed to the amount of
active ingredient (that is the non-diluent portion of the
ingredient). The weight percent (wt %) indicated below is based on
the total weight of the lubricating oil composition.
[0176] When lubricating oil compositions contain one or more of the
additives discussed above, the additive(s) are blended into the
composition in an amount sufficient for it to perform its intended
function. Typical amounts of such additives useful in the present
disclosure are shown to in Table 1 below.
[0177] It is noted that many of the additives are shipped from the
additive manufacturer as a concentrate, containing one or more
additives together, with a certain amount of base oil diluents.
Accordingly, the weight amounts in the table below, as well as
other amounts mentioned herein, are directed to the amount of
active ingredient (that is the non-diluent portion of the
ingredient). The weight percent (wt %) indicated below is based on
the total weight of the lubricating oil composition.
TABLE-US-00002 TABLE 1 Typical Amounts of Other Lubricating Oil
Components Approximate Approximate Compound wt % (Useful) wt %
(Preferred) Antiwear 0.1-2 0.5-1 Dispersant 0.1-20 0.1-8 Detergent
0.1-20 0.1-8 Antioxidant 0.1-10 0.1-5 Friction Modifier 0.01-10
0.01-1.5 Pour Point Depressant 0.0-5 0.01-1.5 (PPD) Anti-foam Agent
0.001-3 0.001-0.15 Viscosity Index Improver 0.0-8 0.1-6 (pure
polymer basis) Inhibitor and Antirust 0.01-5 0.01-1.5
[0178] The foregoing additives are all commercially available
materials. These additives may be added independently but are
usually precombined in packages which can be obtained from
suppliers of lubricant oil additives. Additive packages with a
variety of ingredients, proportions and characteristics are
available and selection of the appropriate package will take the
requisite use of the ultimate composition into account.
[0179] The following non-limiting examples are provided to
illustrate the disclosure.
EXAMPLES
Test Methods
[0180] In all Examples herein, unless specified otherwise, the
following properties are determined pursuant to the following ASTM
standards:
TABLE-US-00003 Noack Pour Properties KV100 KV40 VI Volatility Point
CCSV ASTM Standard D445 D445 D2270 D5800 D5950 D5293
[0181] Additional bench testing was conducted for the lubricating
oil compositions or formulations of this disclosure. The additional
bench testing included the following: thermo-oxidation engine oil
simulation testing (TEOST 33C-SAE 932837 and SAE 962039).
[0182] Deposit resistance formation of the lubricating oils was
compared using a thermo-oxidation engine oil simulation test (TEOST
33C) measured by ASTM D6335. A good result in the TEOST test is
defined as less than 80 mg, or less than 60 mg, or less than 40 mg,
or less than 30 mg, or less than 20 mg, or less than 10 mg. TEOST
33C performance results correlates directly with high temperature
deposit resistance and engine cleanliness for a lubricating oil.
Hence, the lower the TEOST 33C total deposits in milligrams, the
cleaner the internal engine components of an internal combustion
engine lubricated with the lubricating oil compositions disclosed
herein.
Inventive and Comparative Lubricating Oil Compositions
[0183] Table 2 below compares physical properties of the various
Group I to Group V base stocks used in the comparative and
inventive lubricating oils of the instant disclosure.
TABLE-US-00004 TABLE 2 Base Stock Properties Noack CCS-35C, Pour
Point, Aniline Point, KV40 KV100 VI Loss, % cP .degree. C. .degree.
C. D445 D445 D2270 D5800 D5293 D97 D611 Group 1 - 100N 20.4 4.1 99
26.3 5590 -18 98 Group II - 4.5 cSt 22.9 4.6 114 13.8 4906 -18 113
Group III - GTL4 18.3 4.1 126 11.9 1757 -37 121 Group IV - PAO 4
18.5 4.1 126 11.5 1442 <-60 120 Di-isononyl Phthalate 33.4 5.0
55 13.4 -39 <0 ester - Group V
[0184] FIG. 1 shows deposit results for partial lubricating oil
compositions (no pour point depressant, no antifoam agent, no
viscosity modifier or other lubricating oil additives) in order to
assess the impact of base stock type, ashless organic friction
modifier and overbased detergent on cleanliness performance. The
partial lubricating oil compositions of FIG. 1 include both
comparative examples and inventive examples in order to determine
the impact of the ashless organic friction modifier (mixed mono
(47%), di (33%) and tri (20%) fatty acids using saturated C.sub.16
and C.sub.18 alkyl chains) in each of the inventive examples on the
high temperature cleanliness performance as measured by the TEOST
33C deposit test. Each of the inventive lubricating oil
compositions of FIG. 1 also included a high TBN (350 TBN) calcium
salicylate detergent at 2 wt. %. Five different base stocks were
evaluated in the examples of FIG. 1 including a Group I-100
Neutral, a 4.5 cSt Group II, a 4 cSt Group III GTL, a 4 cSt Group
IV PAO, and a Group V di-isononyl phthalate ester. For all five
base stock types, it can be seen that when a combination of the
ashless organic friction modifier (mixed mono (47%), di (33%) and
tri (20%) fatty acids using saturated C.sub.16 and C.sub.18 alkyl
chains) and 350 TBN calcium salicylate detergent were used in the
partial formulations, the TEOST 33C deposit resistance is
significantly lower than if either the ashless organic friction
modifier or the overbased detergent or both were left out of the
lubricating oil compositions. Hence, the surprising benefit in
deposit resistance when the lubricating oils included a synergistic
combination of the ashless organic friction modifier and the
overbased detergent. It can be seen from FIG. 1 that lubricating
oil compositions including a combination of the high TBN calcium
salicylate detergent and the ashless organic friction modifier
(mixed mono (47%), di (33%) and tri (20%) fatty acids using
saturated C.sub.16 and C.sub.18 alkyl chains) provided for TEOST
33C deposits that were from 32 to 91% lower than comparable
(comparative) lubricating oil compositions not including the
ashless organic friction modifier. The improvement in deposit
resistance for the inventive examples of FIG. 1 relative to the
comparative examples not including the combination of the ashless
organic friction modifier and the overbased detergent was
surprising and unexpected. The improvement in deposit resistance
and cleanliness performance was also seen across all five groups of
base stocks tested.
[0185] FIG. 2 shows deposit results for partial lubricating oil
compositions (no pour point depressant, no antifoam agent, no
viscosity modifier or other lubricating oil additives) in order to
assess the impact of overbased detergent type in combination with
ashless organic friction modifier on cleanliness performance. The
base stock used for all of the partial formulations was 4 cSt PAO.
The five overbased detergents evaluated in FIG. 2 included 350 TBN
calcium salicylate, 400 TBN magnesium sulfonate, 400 TBN calcium
sulfonate, 255 TBN calcium phenate, and 68 TBN calcium salicylate.
For all five overbased detergents, it can be seen that when a
combination of the ashless organic friction modifier (mixed mono
(47%), di (33%) and tri (20%) fatty acids using saturated C16 and
C18 alkyl chains) and any of the five overbased detergents were
used in the partial formulations, the TEOST 33C deposit resistance
is significantly lower than if either the ashless organic friction
modifier or the overbased detergent or both were left out of the
lubricating oil compositions. Hence, further support for the
surprising benefit in deposit resistance when the lubricating oils
included a synergistic combination of the ashless organic friction
modifier and the overbased detergent across a range of different
overbased detergent types. The improvement in deposit resistance
for the inventive examples of FIG. 2 ranged from 17 to 80% lower
than comparable comparative examples not including the combination
of the ashless organic friction modifier and the overbased
detergent. Hence, the improvement in deposit resistance and
cleanliness performance was seen across all five types of overbased
detergents tested.
[0186] FIG. 3 shows deposit results for partial lubricating oil
compositions (no pour point depressant, no antifoam agent, no
viscosity modifier or other lubricating oil additives) in order to
assess the impact of ashless organic friction modifier type in
combination with a 350 TBN calcium salicylate detergent on
cleanliness performance. The base stock used for all of the partial
formulations was 4 cSt PAO. The nine different ashless organic
friction modifiers evaluated in FIG. 3 included mixed mono-(47%),
di-(33%) and tri-(20%) fatty acids using saturated C16 and C18
alkyl chains, glycerol mono-, di- and tri-mixed oleate, propylene
glycol stearyl ether, poly-hydroxylcarboxylic acid esters of
polyalkylene oxide modified polyols, n-tallow 1,3 diaminopropane,
oleic acid, oleyl amide, and polymeric organic friction modifier
containing PIBSA, glycerol and oligomerized ethylene oxide. The
composition of the glycerol mono-, di- and tri-mixed oleate
utilized was determined by GC-MS analysis with the analysis results
indicated in the Table 3 below, which shows that it is mainly
glycerol dioleate.
TABLE-US-00005 TABLE 3 Glycerol Mixed Oleate Compositional Analysis
GLYCEROL MIXED OLEATE Wt. % (value in parentheses Area % based on
GC-MS based on GPC trace) Ocatdecadienoic acid 6.3 Glycerol
monooleate 13.3 (16.2) Glycerol dioleate 42.3 (42.6) Triglycerides
14.5 Other 23.6 (41.2 - including triglycerides)
[0187] For all nine ashless organic friction modifiers evaluated,
it can be seen that when a combination of any of one of the nine
ashless organic friction modifiers was used in combination with a
350 TBN calcium salicylate detergent in the partial formulations,
the TEOST 33C deposit resistance is significantly lower than if
either the ashless organic friction modifier or the overbased
detergent or both were left out of the lubricating oil
compositions. Hence, further support for the surprising benefit in
deposit resistance when the lubricating oils included a synergistic
combination of the ashless organic friction modifier and the
overbased detergent across a range of different ashless organic
friction modifier types. The improvement in deposit resistance for
the inventive examples of FIG. 3 ranged from 14 to 88% lower than
comparable comparative examples not including the combination of
the ashless organic friction modifier and the overbased detergent.
Hence, the improvement in deposit resistance and cleanliness
performance was seen across all nine types of ashless organic
friction modifiers tested.
[0188] FIG. 4 (tabular form) and FIG. 5 (graphical form) show
deposit results for partial lubricating oil compositions (no pour
point depressant, no antifoam agent, no viscosity modifier or other
lubricating oil additives) in order to assess the impact of ashless
organic friction modifier loading level or concentration on
cleanliness performance. The ashless organic friction modifier
evaluated was a mixed mono-(47%), di-(33%) and tri-(20%) fatty
acids using saturated C16 and C18 alkyl chains across a loading
range in the partial formulation of 0 to 1 wt. %. The detergent
used was 350 TBN calcium salicylate detergent at 2 wt. %. The base
stock used for all of the partial formulations was 4 cSt PAO. It
can be seen from FIGS. 4 and 5 that the TEOST 33C deposits decrease
as the loading level of the mixed mono-(47%), di-(33%) and
tri-(20%) fatty acids using saturated C16 and C18 alkyl chains
ashless organic friction modifier increases in the inventive
formulations. Relative to the comparative examples in FIG. 4, which
do not include both the ashless organic friction modifier and the
overbased detergent, the inventive examples provided a 21% to 91%
decrease in TEOST 33C deposits, which is surprising and
unexpected.
[0189] In summary, it has been discovered that by employing a
combination of an ashless organic friction modifier and an
overbased detergent in lubricating oil formulations, high deposit
resistance is improved significantly in comparison to comparable
lubricating oils not including a combination of the ashless organic
friction modifier and the overbased detergent.
PCT and EP Clauses:
[0190] 1. A lubricating oil composition comprising:
[0191] a lubricating oil base stock at from 20 to 95 wt % of the
composition, at least one ashless organic friction modifier at from
0.1 to 20 wt % of the composition, at least one overbased detergent
at from 0.1 to 20 wt % of the composition, and wherein the
remainder of the lubricating oil composition includes one or more
other lubricating oil additives;
[0192] wherein the at least one ashless organic friction modifier
is selected from the group consisting of
##STR00017##
wherein A and B are each independently H, a C1-C24 alkyl, or a
C2-C24 alkenyl;
##STR00018##
wherein A, B and C are each independently H, a C1-C24 alkyl, a
C2-C24 alkenyl, a C1-C24 alkylcarbonyl, and a C1-C24
alkenylcarbonyl;
##STR00019##
wherein A is a C1-C24 alkyl, or a C2-C24 alkenyl and B is O, an
amino, a C1-C8 alkylamino or a C1-C8 dialkylamino;
[0193] n-tallow 1,3 diaminopropane; a polymeric organic friction
modifier containing PIBSA, glycerol and oligomerized ethylene oxide
and combinations thereof; and
[0194] wherein the deposit resistance as measured by TEOST 33C
total deposits (ASTM D6335) is at least 20% lower than the deposit
resistance for a comparable lubricating oil composition not
including the combination of the at least one ashless organic
friction modifier and the at least one overbased detergent.
[0195] 2. The composition of clause 1, wherein the lubricating oil
base stock is selected from the from the group consisting of a
Group I base stock, a Group II base stock, a Group III base stock,
a Group IV base stock, a Group V base stock and combinations
thereof.
[0196] 3. The composition of clauses 1-2, wherein the lubricating
oil base stock is from 85 to 95 wt % of the lubricating oil
composition.
[0197] 4. The composition of clauses 1-3, wherein the lubricating
oil base stock is selected from the group consisting of a 100N
Group I base stock, a 4.5 cSt Group II base stock, a 4 cSt gas to
liquids (GTL) base stock, a 4 cSt polyalphaolefin (PAO) base stock,
a di-isononyl phthalate ester base stock and combinations
thereof.
[0198] 5. The composition of clauses 1-4, wherein the at least one
overbased detergent is metal containing detergent including
sulfonates, phenates, salicylates, carboxylates and combinations
thereof and having a Total Base Number (TBN) ranging between 60 and
600.
[0199] 6. The composition of clause 5, wherein the at least one
overbased detergent is selected from the group consisting of 350
TBN calcium salicylate, 400 TBN magnesium sulfonate, 400 TBN
calcium sulfonate, 255 TBN calcium phenate, 68 TBN calcium
salicylate and combinations thereof.
[0200] 7. The composition of clauses 1-6, wherein the at least one
ashless organic friction modifier is selected from the group
consisting of mixed mono-(47%), di-(33%) and tri-(20%) fatty acids
using saturated C16 and C18 alkyl chains, glycerol mono-, di- and
tri-mixed oleate, propylene glycol stearyl ether,
poly-hydroxylcarboxylic acid esters of polyalkylene oxide modified
polyols, oleic acid, oleyl amide, and combinations thereof.
[0201] 8. The composition of clause 7, wherein the at least one
ashless organic friction modifier is mixed mono-(47%), di-(33%) and
tri-(20%) fatty acids using saturated C16 and C18 alkyl chains at
from 0.1 to 2.0 wt % of the lubricating oil composition.
[0202] 9. The composition of clauses 1-8, wherein the deposit
resistance as measured by TEOST 33C total deposits (ASTM D6335) is
less than or equal to 75 mg.
[0203] 10. The composition of clauses 1-9, wherein the one or more
other lubricating oil additives are selected from the group
consisting of an anti-wear additive, viscosity index improver,
antioxidant, dispersant, pour point depressant, corrosion
inhibitor, metal deactivator, seal compatibility additive,
anti-foam agent, inhibitor, anti-rust additive, and ash forming
metal containing friction modifier.
[0204] 11. The composition of clause 10, wherein the one or more
other lubricating oil additives range from 1 to 10 wt % of the
lubricating oil composition and include a combination of a
PIBSA/PAM dispersant, a C3/C6 secondary ZDDP antiwear additive, and
a diphenylamine antioxidant.
[0205] 12. The composition of clauses 1-11, wherein the lubricating
oil base stock has a kinematic viscosity at 100 deg. C. ranging
from 2.5 to 12 cSt.
[0206] 13. The composition of clauses 1-12, wherein lubricating oil
composition is an SAE viscosity grade selected from the group
consisting of 0W-30, 5W-30, 0W-20, 5W-20, 0W-16, 5W-16, 0W-12,
5W-12, 0W-8, and 5W-8.
[0207] 14. The composition of clauses 1-13, wherein the lubricating
oil composition is a passenger vehicle engine oil (PVEO) or a
commercial vehicle engine oil (CVEO).
[0208] 15. A method for improving the high temperature deposit
resistance of a lubricating oil composition for use in lubricating
a mechanical component comprising:
[0209] providing a lubricating oil composition to a mechanical
component, wherein the lubricating oil composition comprises: a
lubricating oil base stock at from 20 to 95 wt % of the
composition, at least one ashless organic friction modifier at from
0.1 to 20 wt % of the composition, at least one overbased detergent
at from 0.1 to 20 wt % of the composition, and wherein the
remainder of the lubricating oil composition includes one or more
other lubricating oil additives;
[0210] wherein the at least one ashless organic friction modifier
is selected from the group consisting of
##STR00020##
wherein A and B are each independently H, a C1-C24 alkyl, or a
C2-C24 alkenyl;
##STR00021##
wherein A, B and C are each independently H, a C1-C24 alkyl, a
C2-C24 alkenyl, a C1-C24 alkylcarbonyl, and a C1-C24
alkenylcarbonyl;
##STR00022##
wherein A is a C1-C24 alkyl, or a C2-C24 alkenyl and B is O, an
amino, a C1-C8 alkylamino or a C1-C8 dialkylamino;
[0211] n-tallow 1,3 diaminopropane;
[0212] a polymeric organic friction modifier containing PIBSA,
glycerol and oligomerized ethylene oxide and combinations thereof;
and [0213] wherein the deposit resistance as measured by TEOST 33C
total deposits (ASTM D6335) is at least 20% lower than the deposit
resistance for a comparable lubricating oil composition not
including the combination of the at least one ashless organic
friction modifier and the at least one overbased detergent.
[0214] All patents and patent applications, test procedures (such
as ASTM methods, UL methods, and the like), and other documents
cited herein are fully incorporated by reference to the extent such
disclosure is not inconsistent with this disclosure and for all
jurisdictions in which such incorporation is permitted.
[0215] When numerical lower limits and numerical upper limits are
listed herein, ranges from any lower limit to any upper limit are
contemplated. While the illustrative embodiments of the disclosure
have been described with particularity, it will be understood that
various other modifications will be apparent to and can be readily
made by those skilled in the art without departing from the spirit
and scope of the disclosure. Accordingly, it is not intended that
the scope of the claims appended hereto be limited to the examples
and descriptions set forth herein but rather that the claims be
construed as encompassing all the features of patentable novelty
which reside in the present disclosure, including all features
which would be treated as equivalents thereof by those skilled in
the art to which the disclosure pertains.
[0216] The present disclosure has been described above with
reference to numerous embodiments and specific examples. Many
variations will suggest themselves to those skilled in this art in
light of the above detailed description. All such obvious
variations are within the full intended scope of the appended
claims.
* * * * *
References