U.S. patent application number 14/104035 was filed with the patent office on 2014-07-10 for method for improving engine fuel efficiency.
This patent application is currently assigned to ExxonMobil Research and Engineering Company. The applicant listed for this patent is ExxonMobil Research and Engineering Company. Invention is credited to David Joseph Baillargeon, Smruti A. Dance, Douglas Edward Deckman.
Application Number | 20140194333 14/104035 |
Document ID | / |
Family ID | 49943556 |
Filed Date | 2014-07-10 |
United States Patent
Application |
20140194333 |
Kind Code |
A1 |
Dance; Smruti A. ; et
al. |
July 10, 2014 |
METHOD FOR IMPROVING ENGINE FUEL EFFICIENCY
Abstract
A method for improving fuel efficiency, while maintaining or
improving high temperature wear, deposit and varnish control, in an
engine lubricated with a lubricating oil by using as the
lubricating oil a formulated oil. The formulated oil has a
composition including a lubricating oil base stock as a major
component, and at least one alkoxylated alcohol as a minor
component. Fuel efficiency is improved and high temperature wear,
deposit and varnish control are maintained or improved as compared
to high temperature wear, deposit and varnish control achieved
using a lubricating engine oil containing a minor component other
than the at least one alkoxylated alcohol. A lubricating engine oil
having a composition including a lubricating oil base stock as a
major component, and at least one alkoxylated alcohol as a minor
component. The lubricating engine oils are useful in internal
combustion engines including direct injection, gasoline and diesel
engines.
Inventors: |
Dance; Smruti A.;
(Robbinsville, NJ) ; Deckman; Douglas Edward;
(Mullica Hill, NJ) ; Baillargeon; David Joseph;
(Cherry Hill, NJ) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ExxonMobil Research and Engineering Company |
Annandale |
NJ |
US |
|
|
Assignee: |
ExxonMobil Research and Engineering
Company
Annandale
NJ
|
Family ID: |
49943556 |
Appl. No.: |
14/104035 |
Filed: |
December 12, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61748776 |
Jan 4, 2013 |
|
|
|
Current U.S.
Class: |
508/580 ;
508/579 |
Current CPC
Class: |
C10M 131/10 20130101;
C10M 2219/068 20130101; C10M 2207/046 20130101; C10N 2030/04
20130101; C10N 2060/14 20130101; C10N 2030/42 20200501; C10M
2209/104 20130101; C10M 2215/28 20130101; C10M 2209/107 20130101;
C10M 2209/062 20130101; C10M 2207/126 20130101; C10M 2215/064
20130101; C10M 169/041 20130101; C10M 2207/026 20130101; C10M
2219/046 20130101; C10M 2223/00 20130101; C10M 2209/103 20130101;
C10M 2205/0285 20130101; C10M 2209/106 20130101; C10N 2030/45
20200501; C10M 169/04 20130101; C10N 2030/08 20130101; C10M 169/044
20130101; C10M 2205/04 20130101; C10N 2030/52 20200501; C10M
2209/105 20130101; C10M 2223/045 20130101; C10M 2207/2805 20130101;
C10N 2030/06 20130101; C10M 2207/262 20130101; C10M 2229/02
20130101; C10M 2203/1006 20130101; C10N 2030/54 20200501; C10M
2203/1025 20130101; C10M 145/36 20130101; C10M 2209/084 20130101;
C10M 2209/103 20130101; C10M 2209/108 20130101; C10M 2219/068
20130101; C10N 2010/12 20130101; C10M 2205/04 20130101; C10M
2205/06 20130101; C10M 2203/1025 20130101; C10N 2020/02 20130101;
C10M 2209/105 20130101; C10M 2209/108 20130101; C10M 2209/106
20130101; C10M 2209/108 20130101; C10M 2209/104 20130101; C10M
2209/105 20130101; C10M 2209/108 20130101; C10M 2209/107 20130101;
C10M 2209/108 20130101; C10M 2219/046 20130101; C10N 2010/04
20130101; C10M 2207/262 20130101; C10N 2010/04 20130101; C10M
2215/28 20130101; C10N 2060/14 20130101; C10M 2209/062 20130101;
C10M 2209/086 20130101; C10M 2223/045 20130101; C10N 2010/04
20130101; C10M 2219/068 20130101; C10N 2010/12 20130101; C10M
2219/046 20130101; C10N 2010/04 20130101; C10M 2207/262 20130101;
C10N 2010/04 20130101; C10M 2223/045 20130101; C10N 2010/04
20130101; C10M 2203/1025 20130101; C10N 2020/02 20130101; C10M
2215/28 20130101; C10N 2060/14 20130101 |
Class at
Publication: |
508/580 ;
508/579 |
International
Class: |
C10M 129/16 20060101
C10M129/16 |
Claims
1. A method for improving fuel efficiency, while maintaining or
improving high temperature wear, deposit and varnish control, in an
engine lubricated with a lubricating oil by using as the
lubricating oil a formulated oil, said formulated oil having a
composition comprising a lubricating oil base stock as a major
component; and at least one alkoxylated alcohol, as a minor
component; wherein fuel efficiency is improved and high temperature
wear, deposit and varnish control are maintained or improved as
compared to high temperature wear, deposit and varnish control
achieved using a lubricating engine oil containing a minor
component other than the at least one alkoxylated alcohol.
2. The method of claim 1 wherein the lubricating oil base stock
comprises a Group I, Group II, Group III, Group IV or Group V base
oil.
3. The method of claim 1 wherein, in comparison with fuel
efficiency achieved using a lubricating engine oil containing a
minor component other than the at least one alkoxylated alcohol,
the lubricating engine oil containing at least one alkoxylated
alcohol exhibits a fuel efficiency, FEI sum, greater than
1.2.times., as determined by a Sequence VID Fuel Economy (ASTM
D7589) engine test; and wherein, in comparison with high
temperature wear, deposit and varnish control achieved using a
lubricating engine oil containing a minor component other than the
at least one alkoxylated alcohol, the lubricating engine oil
containing at least one alkoxylated alcohol exhibits high
temperature wear, deposit and varnish control greater than
1.1.times., as determined by a Sequence IIIG/IIIGA (ASTM D7320)
engine test.
4. The method of claim 1 wherein the alkoxylated alcohol is
represented by the formula R.sup.1--[O--(CH.sub.2).sub.x].sub.y--OH
wherein R.sup.1 is a hydrocarbon group having from 1 to 50 carbon
atoms, x is an integer from 1 to 10, and y is an integer from 1 to
10.
5. The method of claim 4 wherein the alkoxylated alcohol is
selected from stearyl alcohol ethoxylate, lauryl alcohol
ethoxylate, oleyl alcohol ethoxylate, stearyl alcohol propoxylate,
lauryl alcohol propoxylate, oleyl alcohol propoxylate, stearyl
alcohol butoxylate, octyl alcohol butoxylate, myristyl alcohol
ethoxypropoxylate, stearyl alcohol ethoxypropoxylate, lauryl
alcohol ethoxypropoxylate, and mixtures thereof.
6. The method of claim 1 wherein the alkoxylated alcohol is
represented by the formula R.sup.2O--(R.sup.3--O--).sub.zH wherein
R.sup.2 is a branched or linear hydrocarbon group having from 12 to
20 carbon atoms, R.sup.3 is an alkylene group having from 2 to 4
carbon atoms, and z is an integer from 1 to 10.
7. The method of claim 6 wherein the alkoxylated alcohol is
selected from polyoxyethylene stearyl ether, polyoxyethylene lauryl
ether, polyoxyethylene oleyl ether, polyoxypropylene stearyl ether,
polyoxypropylene lauryl ether, polyoxypropylene oleyl ether,
polyoxybutylene stearyl ether, polyoxybutylene octyl ether,
poly(oxyethylene)(oxypropylene) myristyl ether,
poly(oxyethylene)(oxypropylene) stearyl ether,
poly(oxyethylene)(oxypropylene) lauryl ether, and mixtures
thereof.
8. The method of claim 1 wherein the oil base stock is present in
an amount of from 70 weight percent to 95 weight percent, and the
at least one alkoxylated alcohol is present in an amount of from
0.05 weight percent to 6 weight percent, based on the total weight
of the formulated oil.
9. The method of claim 1 wherein, in friction measurements of the
lubricating oil by mini-traction machine (MTM) in Striheck mode at
50.degree. C. and 100.degree. C., the integrated Stribeck friction
coefficient of the lubricating oil in the MTM is reduced as
compared to the integrated Stribeck friction coefficient of a
lubricating oil containing a minor component other than the at
least one alkoxylated alcohol.
10. The method of claim 1 wherein phosphorus retention is improved
as compared to phosphorus retention achieved using a lubricating
engine oil containing a minor component other than the at least one
alkoxylated alcohol.
11. A lubricating engine oil having a composition comprising a
lubricating oil base stock as a major component; and at least one
alkoxylated alcohol, as a minor component; wherein fuel efficiency
is improved and high temperature wear, deposit and varnish control
are maintained or improved as compared to high temperature wear,
deposit and varnish control achieved using a lubricating engine oil
containing a minor component other than the at least one
alkoxylated alcohol.
12. The lubricating engine oil of claim 11 wherein the lubricating
oil base stock comprises a Group I, Group II, Group III, Group IV
or Group V base oil.
13. The lubricating engine oil of claim 11 wherein, in comparison
with fuel efficiency achieved using a lubricating engine oil
containing a minor component other than the at least one
alkoxylated alcohol, the lubricating engine oil containing at least
one alkoxylated alcohol exhibits a fuel efficiency, FEI sum,
greater than 1.2.times., as determined by a Sequence YID Fuel
Economy (ASTM D7589) engine test; and wherein, in comparison with
high temperature wear, deposit and varnish control achieved using a
lubricating engine oil containing a minor component other than the
at least one alkoxylated alcohol, the lubricating engine oil
containing at least one alkoxylated alcohol exhibits high
temperature wear, deposit and varnish control greater than
1.1.times., as determined by a Sequence IIIG/IIIGA (ASTM D7320)
engine test.
14. The lubricating engine oil of claim 11 wherein the alkoxylated
alcohol is represented by the formula
R.sup.1--[O--(CH.sub.2).sub.x].sub.y--OH wherein R.sup.1 is a
hydrocarbon group having from 1 to 50 carbon atoms, x is an integer
from 1 to 10, and y is an integer from 1 to 10.
15. The lubricating engine oil of claim 14 wherein the alkoxylated
alcohol is selected from stearyl alcohol ethoxylate, lauryl alcohol
ethoxylate, oleyl alcohol ethoxylate, stearyl alcohol propoxylate,
lauryl alcohol propoxylate, oleyl alcohol propoxylate, stearyl
alcohol butoxylate, octyl alcohol butoxylate, myristyl alcohol
ethoxypropoxylate, stearyl alcohol ethoxypropoxylate, and lauryl
alcohol ethoxypropoxylate.
16. The lubricating engine oil of claim 11 wherein the alkoxylated
alcohol is represented by the formula
R.sup.2O--(R.sup.3--O--).sub.zH wherein R.sup.2 is a hydrocarbon
group having from 12 to 20 carbon atoms, R.sup.3 is an alkylene
group having from 2 to 4 carbon atoms, and z is an integer from 1
to 10.
17. The lubricating engine oil of claim 16 wherein the alkoxylated
alcohol is selected from polyoxyethylene stearyl ether,
polyoxyethylene lauryl ether, polyoxyethylene oleyl ether,
polyoxypropylene stearyl ether, polyoxypropylene lauryl ether,
polyoxypropylene oleyl ether, polyoxybutylene stearyl ether,
polyoxybutylene octyl ether, poly(oxyethylene)(oxypropylene)
myristyl ether, poly(oxyethylene)(oxypropylene) stearyl ether, and
poly(oxyethylene)(oxypropylene) lauryl ether.
18. The lubricating engine oil of claim 11 wherein the oil base
stock is present in an amount of from 70 weight percent to 95
weight percent, and the at least one alkoxylated alcohol is present
in an amount of from 0.05 weight percent to 6 weight percent, based
on the total weight of the formulated oil.
19. The lubricating engine oil of claim 11 wherein the lubricating
oil further comprises one or more of an anti-wear additive,
viscosity index improver, antioxidant, detergent, dispersant, pour
point depressant, corrosion inhibitor, metal deactivator, seal
compatibility additive, anti-foam agent, inhibitor, and anti-rust
additive.
20. The lubricating engine oil of claim 11 wherein the lubricating
oil is a passenger vehicle engine oil (PVEO).
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional
Application Ser. No. 61/748,776 filed Jan. 4, 2013, herein
incorporated by reference in its entirety.
FIELD
[0002] This disclosure relates to improving fuel efficiency, while
maintaining or improving high temperature performance (e.g., high
temperature wear, deposit and varnish control), in an engine
lubricated with a lubricating oil by including an alkoxylated
alcohol component, in the lubricating oil.
BACKGROUND
[0003] Fuel efficiency requirements for passenger vehicles are
becoming increasingly more stringent. New legislation in the United
States and European Union within the past few years has set fuel
economy and emissions targets not readily achievable with today's
vehicle and lubricant technology.
[0004] To address these increasing standards, automotive original
equipment manufacturers are demanding better fuel economy as a
lubricant-related performance characteristic, while maintaining
deposit control and oxidative stability requirements. One well
known way to increase fuel economy is to decrease the viscosity of
the lubricating oil. However, this approach is now reaching the
limits of current equipment capabilities and specifications. At a
given viscosity, it is well known that adding organic or
organo-metallic friction modifiers reduces the surface friction of
the lubricating oil and allows for better fuel economy. However
these additives often bring with them detrimental effects such as
increased deposit formation, seals impacts, or they out-compete the
anti-wear components for limited surface sites, thereby not
allowing the formation of an anti-wear film, causing increased
wear.
[0005] Contemporary lubricants such as engine oils use mixtures of
additives such as dispersants, detergents, inhibitors, viscosity
index improvers and the like to provide engine cleanliness and
durability under a wide range of performance conditions of
temperature, pressure, and lubricant service life.
[0006] Lubricant-related performance characteristics such as high
temperature deposit control, high temperature varnish control, and
fuel economy are extremely advantageous attributes as measured by a
variety of bench and engine tests. As indicated above, it is known
that adding organic friction modifiers to a lubricant formulation
imparts frictional benefits at low temperatures, consequently
improving the lubricant fuel economy performance. At high
temperatures, however, adding increased levels of organic friction
modifier can invite high temperature performance issues. For
example, excessive wear, deposits, and varnish are undesirable
consequences of high levels of friction modifier in an engine oil
formulation at high temperature engine operation.
[0007] U.S. Patent Application Publication No. 2005/0101497
discloses the use of an alkoxylated alcohol, both as an independent
additive or in conjunction with one or more other additives, as a
friction modifier that resists deterioration and achieves improved
friction and friction durability. Power transmission fluids are
disclosed that provide improved or lower static friction while
maintaining dynamic friction, thus controlling (or decreasing)
friction in a stable manner. The power transmission fluids comprise
a major amount of a base oil and a minor amount of at least one
alkoxylated alcohol.
[0008] A major challenge in engine oil formulation is
simultaneously achieving high temperature wear, deposit, and
varnish control while also achieving improved fuel economy.
[0009] Despite the advances in lubricant oil formulation
technology, there exists a need for an engine oil lubricant that
effectively improves fuel economy while maintaining or improving
antiwear performance (e.g., high temperature wear, deposit and
varnish control).
SUMMARY
[0010] This disclosure relates in part to a method for improving
fuel efficiency, while maintaining or improving wear protection
(e.g., high temperature wear, deposit and varnish control), in an
engine lubricated with a lubricating oil by including at least one
alkoxylated alcohol in the lubricating oil. The lubricating oils of
this disclosure are useful in internal combustion engines including
direct injection, gasoline and diesel engines.
[0011] This disclosure also relates in part to a method for
improving fuel efficiency, while maintaining or improving high
temperature wear, deposit and varnish control, in an engine
lubricated with a lubricating oil by using as the lubricating oil a
formulated oil. The formulated oil has a composition comprising a
lubricating oil base stock as a major component; and at least one
alkoxylated alcohol, as a minor component. Fuel efficiency is
improved and high temperature wear, deposit and varnish control are
maintained or improved as compared to high temperature wear,
deposit and varnish control achieved using a lubricating engine oil
containing a minor component other than the at least one
alkoxylated alcohol.
[0012] This disclosure further relates in part to a lubricating
engine oil having a composition comprising a lubricating oil base
stock as a major component; and at least one alkoxylated alcohol,
as a minor component. Fuel efficiency is improved and high
temperature wear, deposit and varnish control are surprisingly
maintained or improved as compared to high temperature wear,
deposit and varnish control achieved using a lubricating engine oil
containing a minor component other than the at least one
alkoxylated alcohol.
[0013] It has been surprisingly found that, in accordance with this
disclosure, improvements in fuel economy are obtained without
sacrificing engine durability (e.g., while maintaining or improving
high temperature wear, deposit and varnish control) in an engine
lubricated with a lubricating oil, by including at least one
alkoxylated alcohol in the lubricating oil.
[0014] Other objects and advantages of the present disclosure will
become apparent from the detailed description that follows.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 shows formulation details in weight percent based on
the total weight percent of the formulation, of formulations used
in the Examples.
[0016] FIG. 2 shows the results of bench and engine testing of the
formulations used in the Examples.
[0017] FIG. 3 shows MTM Stribeck curves from the Reference 1
formulation and the Example 3 formulation finished oil performance
in MTM Stribeck test at 50.degree. C. (log and mean speed).
[0018] FIG. 4 shows MTM Stribeck curves from the Reference 1
formulation and the Example 3 formulation finished oil performance
in MTM Stribeck test at 100.degree. C. (log and mean speed).
[0019] FIG. 5 shows formulation details in weight percent based on
the total weight percent of the formulation, of the Reference 3
formulation and the Example 6 formulation. FIG. 5 also shows the
results of bench and engine testing of the Reference 3 formulation
and the Example 6 formulation.
[0020] FIG. 6 shows formulation details in weight percent based on
the total weight percent of the formulation, of the Reference 1, 4
and 5 formulations and the Example 7 and 8 formulations. FIG. 6
also shows the results of bench and engine testing of the Reference
1, 4 and 5 formulations and the Example 7 and 8 formulations.
[0021] FIG. 7 shows formulation details in weight percent based on
the total weight percent of the formulation, of the Example 9 and
10 formulations. FIG. 7 also shows the results of bench testing of
the Example 9 and 10 formulations.
[0022] FIG. 8 shows formulation details in weight percent based on
the total weight percent of the formulation, of the Example 11-22
formulations.
[0023] FIG. 9 shows formulation details in weight percent based on
the total weight percent of the formulation, of the Example 23-34
formulations.
[0024] FIG. 10 shows formulation details in weight percent based on
the total weight percent of the formulation, of the Example 35-46
formulations.
[0025] FIG. 11 shows formulation details in weight percent based on
the total weight percent of the formulation, of the Example 47-58
formulations.
DETAILED DESCRIPTION
[0026] 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.
[0027] It has now been found that improved fuel efficiency can be
attained, while wear protection is unexpectedly maintained or
improved (e.g., high temperature wear, deposit and varnish
control), in an engine lubricated with a lubricating oil by using
as the lubricating oil a formulated oil that has one or more
alkoxylated alcohols. The formulated oil preferably comprises a
lubricating oil base stock as a major component, and a metal
dialkyl dithio phosphate, at least one alkoxylated alcohol, and a
viscosity index improver, as minor components. The lubricating oils
of this disclosure are particularly advantageous as passenger
vehicle engine oil (PVEO) products.
[0028] The lubricating oils of this disclosure provide excellent
engine protection including friction reduction and anti-wear
performance. This benefit has been demonstrated for the lubricating
oils of this disclosure in the Sequence IIIG/IIIGA (ASTM D7320) and
Sequence VID (ASTM D7589) engine tests. The lubricating oils of
this disclosure provide improved fuel efficiency. A lower HTHS
viscosity engine oil generally provides superior fuel economy to a
higher HTHS viscosity product. This benefit has been demonstrated
for the lubricating oils of this disclosure in the Sequence VID
Fuel Economy (ASTM D7589) engine test.
[0029] The lubricating engine oils of this disclosure have a
composition sufficient to pass wear protection requirements of one
or more engine tests selected from Sequence IIIG, Sequence VID, and
others.
[0030] In comparison with fuel efficiency achieved using a
lubricating engine oil containing a minor component other than the
at least one alkoxylated alcohol, the lubricating engine oils
containing at least one alkoxylated alcohol of this disclosure can
exhibit a fuel efficiency preferably greater than 1.2.times., and
more preferably greater than 1.3.times., as determined by the
Sequence VID Fuel Economy (ASTM D7589) engine test. In an
embodiment, in comparison with fuel efficiency achieved using a
lubricating engine oil containing a minor component other than the
at least one alkoxylated alcohol, the lubricating engine oils
containing at least one alkoxylated alcohol of this disclosure can
exhibit a fuel efficiency greater than 1.4.times., preferably
greater than 1.5.times., and more preferably greater than
1.6.times., as determined by the Sequence VID Fuel Economy (ASTM
D7589) engine test.
[0031] In comparison with high temperature wear, deposit and
varnish control achieved using a lubricating engine oil containing
a minor component other than the at least one alkoxylated alcohol,
the lubricating engine oils containing at least one alkoxylated
alcohol of this disclosure can exhibit high temperature wear,
deposit and varnish control preferably greater than 1.1.times., and
more preferably greater than 1.2.times., as determined by the
Sequence IIIG/IIIGA (ASTM D7320) engine test. In an embodiment, in
comparison with high temperature wear, deposit and varnish control
achieved using a lubricating engine oil containing a minor
component other than the at least one alkoxylated alcohol, the
lubricating engine oils containing at least one alkoxylated alcohol
of this disclosure can exhibit a high temperature wear, deposit and
varnish control preferably greater than 1.2.times., and more
preferably greater than 1.3.times., as determined by the Sequence
IIIG/IIIGA (ASTM D7320) engine test.
[0032] In an embodiment, in comparison with high temperature wear,
deposit and varnish control achieved using a lubricating engine oil
containing a minor component other than the at least one
alkoxylated alcohol, the lubricating engine oils containing at
least one alkoxylated alcohol of this disclosure can exhibit, at
the same time, both a fuel efficiency greater than 1.4.times.,
preferably greater than 1.5.times., and more preferably greater
than 1.6.times., as determined by the Sequence VID Fuel Economy
(ASTM D7589) engine test, and high temperature wear, deposit and
varnish control preferably greater than 1.2.times., and more
(preferably greater than 1.3.times., as determined by the Sequence
IIIG/IIIGA (ASTM D7320) engine test.
Lubricating Oil Base Stocks
[0033] A wide range of lubricating base oils is known in the art.
Lubricating base oils that are useful in the present disclosure are
both natural oils, and synthetic oils, and unconventional oils (or
mixtures thereof) can be used unrefined, refined, or rerefined (the
latter is also known as reclaimed or reprocessed oil). Unrefined
oils are those obtained directly from a natural or synthetic source
and used without added purification. These include shale oil
obtained directly from retorting operations, petroleum oil obtained
directly from primary distillation, and ester oil obtained directly
from an esterification process. Refined oils are similar to the
oils discussed for unrefined oils except refined oils are subjected
to one or more purification steps to improve at least one
lubricating oil property. One skilled in the art is familiar with
many purification processes. These processes include solvent
extraction, secondary distillation, acid extraction, base
extraction, filtration, and percolation. Rerefined oils are
obtained by processes analogous to refined oils but using an oil
that has been previously used as a feed stock.
[0034] Groups I, II, III, IV and V are broad base oil stock
categories developed and defined by the American Petroleum
Institute (API Publication 1509: wvvw.API.org) to create guidelines
for lubricant base oils. Group I base stocks have a viscosity index
of between 80 to 120 and contain greater than 0.03% sulfur and/or
less than 90% saturates. Group II base stocks have a viscosity
index of between 80 to 120, and contain less than or equal to 0.03%
sulfur and greater than or equal to 90% saturates. Group III stocks
have a viscosity index greater than 120 and contain less than or
equal to 0.03% sulfur and greater than 90% saturates. Group TV
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 Includes
polyalphaolefins (PAO) and GTL products Group V All other base oil
stocks not included in Groups I, II, III or IV
[0035] 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.
[0036] Group II and/or Group III hydroprocessed or hydrocracked
basestocks, including synthetic oils such as polyalphaolefins,
alkyl aromatics and synthetic esters are also well known basestock
oils.
[0037] 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.
[0038] 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 250
to 3,000, although PAO's may be made in viscosities up to 100 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
C.sub.32 alphaolefins with the C.sub.8 to 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 turners 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. Bi-modal mixtures
of PAO fluids having a viscosity range of 1.5 to 100 cSt may be
used if desired.
[0039] 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. No. 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 C.sub.14 to C.sub.18
olefins are described in U.S. Pat. No. 4,218,330.
[0040] 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/thydroisomerization catalyst, such as one of the
specialized lube hydrocracking (LHDC) catalysts or a crystalline
hydrocracking/thydroisomerization 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 hydro
cracked/hydroisomerized waxes are described, for example, in U.S.
Pat. Nos. 2,817,693; 4,975,177; 4,921,594 and to 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.
[0041] 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 3 cSt to 50
cSt, preferably 3 cSt to 30 cSt, more preferably 3.5 cSt to 25 cSt,
as exemplified by GTL 4 with kinematic viscosity of 4.0 cSt at
100.degree. C. and a viscosity index of 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 -20.degree. C. or lower, and under some conditions may have
advantageous pour points of -25.degree. C. or lower, with useful
pour points of -30.degree. C. to -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.
[0042] The hydrocarbyl aromatics can be used as base oil or base
oil component and can be any hydrocarbyl molecule that contains at
least 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 C.sub.6 up to C.sub.60 with a range of C.sub.8 to
C.sub.20 often being preferred. A mixture of hydrocarbyl groups is
often preferred, and up to 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 5% of
the molecule is comprised of an above-type aromatic moiety.
Viscosities at 100.degree. C. of approximately 3 cSt to 50 cSt are
preferred, with viscosities of approximately 3.4 cSt to 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 2% to 25%,
preferably 4% to 20%, and more preferably 4% to 15%, depending on
the application.
[0043] 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 118, 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.
[0044] 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
phthatic 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-ethythexyl alcohol, etc. Specific examples of these types of
esters include dibutyl adipate, di(2-ethylhexyl) sebacate,
di-n-hexyl fumarate, dioctyl sebacate, to dilsooctyl azelate,
diisodecyl azelate, dioctyl phthalate, didecyl phthalate, dieicosyl
sebacate, etc.
[0045] 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, is trimethylol propane,
pentaerythritol and dipentaerythritol) with alkanoic acids
containing at least 4 carbon atoms, preferably C.sub.5 to C.sub.30
acids such as saturated straight chain fatty acids including
caprytic 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.
[0046] 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 5 to 10 carbon atoms. These
esters are widely available commercially, for example, the Mobil
P-41 and P-51 esters of ExxonMobil Chemical Company.
[0047] 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 Mobil P-51 ester of ExxonMobil
Chemical Company.
[0048] Engine oil formulations containing renewable esters are
included in this disclosure. For such formulations, the renewable
content of the ester is typically greater than 70 weight percent,
preferably more than 80 weight percent and most preferably more
than 90 weight percent. Renewable esters can be preferred in
combination with alkoxylated alcohols.
[0049] 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.
[0050] 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
isornerate/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.
[0051] 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 tube
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.
[0052] 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 2 mm.sup.2/s to 50 mm.sup.2/s (ASTM D445).
They are further characterized typically as having pour points of
-5.degree. C. to -40.degree. C. or lower (ASTM D97). They are also
characterized typically as having viscosity indices of 80 to 140 or
greater (ASTM D2270).
[0053] In addition, the GTL base stock(s) and/or base oil(s) are
typically highly paraffinic (>90% saturates), and may contain
mixtures of tnonocycloparaffins and multicycloparaffins in
combination with non-cyclic isoparaffins. The ratio of the
naphthenic 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 10 ppm, and more typically
less than 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 phosphorous and aromatics make this materially
especially suitable for the formulation of low SAP products.
[0054] 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.
[0055] 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).
[0056] 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) and hydrodewaxed, or hyroisomerized/cat
(and/or solvent) dewaxed base stock(s) and/or base oil(s) typically
have very low sulfur and nitrogen content, generally containing
less than 10 ppm, and more typically less than 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
phosphorous and aromatics make this material especially suitable
for the formulation of low sulfur, sulfated ash, and phosphorus
(low SAP) products.
[0057] 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.
[0058] The base oil constitutes the major component of the engine
oil lubricant composition of the present disclosure and typically
is present in an amount ranging from 50 to 99 weight percent,
preferably from 70 to 95 weight percent, and more preferably from
85 to 95 weight percent, based on the total weight of the
composition. The base oil may be selected from any of the synthetic
or natural oils typically used as crankcase lubricating oils for
spark-ignited and compression-ignited engines. The base oil
conveniently has a kinematic viscosity, according to ASTM
standards, of 2.5 cSt to 12 cSt (or mm.sup.2 /s) at 100.degree. C.
and preferably of 2.5 cSt to 9 cSt (or mm.sup.2/s) at 100.degree.
C. 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.
Alkoxylated Alcohols
[0059] The alkoxylated alcohol additive useful in the lubricating
oils of this disclosure is important for improving fuel efficiency,
while maintaining or improving high temperature wear, deposit and
varnish control, in an engine lubricated with the lubricating
oil.
[0060] In an embodiment, an alkoxylated alcohol useful in this
disclosure can be represented by the formula
R.sup.1--[O--(CH.sub.2).sub.x].sub.y--OH (1)
wherein R.sup.1 is a hydrocarbon group having from 1 to 50 carbon
atoms, x is an integer from 1 to 10, and y is an integer from 1 to
10. In formula (1) above, it is understood that the R.sup.1 group
can be a mixture of hydrocarbon groups, for example, some portion
alkyl and some portion aryl.
[0061] R.sup.1 in formula (1) is a hydrocarbyl group, preferably a
straight chain or branched chain alkyl, alkenyl, or alkylaryl
group, and more preferably a linear group. In particular, an alkyl
or alkenyl group having 1 to 20 carbon atoms is preferable, an
alkyl or alkenyl group having 12 to 20 carbon atoms is more
preferable, and a lauryl or oleyl group is the most preferable.
Stearyl or similar groups can also be preferable. These hydrocarbon
groups can be pure or mixtures. Commercially, lauryl and oleyl
groups are mixtures (i.e., mixtures of different isomers or
slightly different chain lengths).
[0062] The integer x ranges from 1 to 10, in other words, an
alkylene group, preferably an alkylene group having 2 to 4 carbon
atoms, e.g., an ethylene, propylene, or butylene group or mixtures.
An addition reaction of alkylene oxide may be homopolymerization,
or random or block copolymerization. As a the compound having a
larger x decreases the solubility to oil and thermal stability, x
is preferably 1 to 5, and more preferably 2 to 4.
[0063] The integer y ranges from 1 to 10, in other words, the
compound may be a monoalkoxylated alcohol or polyalkoxylated
alcohol. As the compound having a larger y decreases the solubility
to oil and thermal stability, y is preferably 1 to 5, and more
preferably 2 to 4.
[0064] illustrative alkoxylated alcohols of formula (1) useful in
this disclosure include, for example, stearyl alcohol ethoxylate,
lauryl alcohol ethoxylate, oleyl alcohol ethoxylate, stearyl
alcohol propoxylate, lauryl alcohol propoxylate, oleyl alcohol
propoxylate, stearyl alcohol butoxylate, octyl alcohol butoxylate,
myristyl alcohol ethoxypropoxylate, stearyl alcohol
ethoxypropoxylate, lauryl alcohol ethoxypropoxylate, or mixtures of
the above, and the like.
[0065] In another embodiment, an alkoxylated alcohol useful in this
disclosure can be represented by the formula
R.sup.2O--(R.sup.3--O--).sub.zH (2)
wherein R.sup.2 is a hydrocarbon group having from 12 to 20 carbon
atoms, R.sup.3 is an alkylene group having from 2 to 4 carbon
atoms, and z is an integer from 1 to 10.
[0066] The alkoxylated alcohols represented by formula (2) are
(poly)oxyalkyleneglycol ethers. R.sup.2 in formula (2) is a
hydrocarbyl group, preferably a straight chain or branched chain
alkyl, alkenyl, or alkylalyl group, and more preferably a linear
group. In particular, an alkyl or alkenyl group having 1 to 20
carbon atoms is preferable, an alkyl or alkenyl group having 12 to
20 carbon atoms is more preferable, and a lauryl or oleyl group is
the most preferable.
[0067] R.sup.3 is an alkylene group, preferably an alkylene group
having 2 to 4 carbon atoms, e.g., an ethylene, propylene, or
butylene group. The (R.sup.3--O--).sub.z portion is obtained by
adding ethylene oxide, propylene oxide, butylene oxide or the like.
An addition reaction of alkylene oxide may be homopolymerization,
or random or block copolymerization.
[0068] Further, z ranges from 1 to 10, in other words, the compound
may be a monooxyalkyleneglycol ether or polyoxyalkyleneglycol
ether. As the compound having a larger z decreases the solubility
to oil and thermal stability, z is preferably 1 to 5, and more
preferably 2 to 4.
[0069] Illustrative alkyl groups include, for example, methyl,
ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl,
isopentyl, neopentyl, tert-pentyl, hexyl, heptyl, octyl,
2-ethylhexyl, nonyl, decyl, undecyl, dodecyl, tridecyl,
isotridecyl, myristyl, stearyl, eicosyl, docosyl, tetracosyl,
triacontyl, 2-octyldodecyl, 2-dodecylhexadecyl,
2-tetradecyloctadecyl, monomethyl-branched isostearyl groups, and
the like.
[0070] Illustrative alkenyl groups include, for example, vinyl,
allyl, propenyl, isopropenyl, butenyl, isobutenyl, pentenyl,
isopentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl,
undecenyl, dodecenyl, tetradecenyl, oleyl groups, and the like.
[0071] Illustrative alkylaryl groups include, for example, phenyl,
tolyl, xylyl, cumenyl, mesityl, benzyl, penethyl, styryl, cinnamyl,
benzhydryl, trityl, propylphenyl, butylphenyl, pentylphenyl,
hexylphenyl, heptylphenyl, octylphenyl, nonylphenyl,
.alpha.-naphthyl, .beta.-naphthyl groups, and the like.
[0072] Illustrative cycloalkyl and cycloalkenyl groups include, for
example, cyclopentyl, cyclohexyl, cyclobutyl, methylcyclopentyl,
methylcyclohexyl, methylcycloheptyl, cyclopentenyl, cyclohexenyl,
cycloheptenyl, methylcyclopentenyl, methylcyclohexenyl,
methylcycloheptenyl, and the like.
[0073] Illustrative alkoxylated alcohols of formula (2) useful in
this disclosure include, for example, polyoxyethylene stearyl
ether, polyoxyethylene lauryl ether, polyoxyethylene oleyl ether,
polyoxypropylene stearyl ether, polyoxypropylene lauryl ether,
polyoxypropylene oleyl ether, polyoxybutylene stearyl ether,
polyoxybutylene octyl ether, poly(oxyethylene)(oxypropylene)
myristyl ether, poly(oxyethylene)(oxypropylene) stearyl ether,
poly(oxyethytene)(oxypropylene) lauryl ether, and the like.
[0074] When a base oil for lubricating oil is used in the
lubricating composition according to the present disclosure, the
alkoxylated alcohol may be used alone or as a mixture of
alkoxylated alcohols. Although the content of the alkoxylated
alcohol is not limited, it is preferably 0.01 to 5 wt %, and more
preferably 0.1 to 1 wt % of the base oil for lubricating oil.
Other Additives
[0075] The formulated lubricating oil useful in the present
disclosure may is additionally contain one or more of the other
commonly used lubricating oil performance additives including but
not limited to antiwear agents, dispersants, other detergents,
corrosion inhibitors, rust inhibitors, metal deactivators, extreme
pressure additives, anti-seizure agents, wax modifiers, viscosity
index improvers, viscosity modifiers, fluid-loss additives, seal
compatibility agents, friction modifiers, lubricity agents,
anti-staining agents, chromophoric agents, defoamants,
demulsifiers, emulsifiers, densifiers, wetting agents, gelling
agents, tackiness agents, colorants, and others. For a review of
many commonly used additives, see Klamann in Lubricants and Related
Products, Verlag Chemie, Deerfield Beach, Fla.; ISBN 0-89573-177-0.
Reference is also made to "Lubricant Additives" by M. W. Ranney,
published by Noyes Data Corporation of Parkridge, N.J. (1973); see
also U.S. Pat. No. 7,704,930, the disclosure of which is
incorporated herein in its entirety.
[0076] 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.
Antiwear Additive
[0077] A metal alkylthiophosphate and more particularly a metal
dialkyl dithio phosphate in which the metal constituent is zinc, or
zinc dialkyl dithio phosphate (ZDDP) is 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. Alkyl
aryl groups may also be used.
[0078] 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".
[0079] The ZDDP is typically used in amounts of from 0.4 weight
percent to 1.2 weight percent, preferably from 0.5 weight percent
to 1.0 weight percent, and more preferably from 0.6 weight percent
to 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 0.6 to 1.0 weight percent of the total weight of the
lubricating oil.
[0080] Low phosphorus engine oil formulations are included in this
disclosure. For such formulations, the phosphorus content is
typically less than 0.12 weight percent preferably less than 0.10
weight percent and most preferably less than 0.085 weight percent.
Low phosphorus can be preferred in combination with alkoxylated
alcohols.
Viscosity Index Improvers
[0081] Viscosity index improvers (also known as VI improvers,
viscosity modifiers, and viscosity improvers) can be included in
the lubricant compositions of this disclosure.
[0082] Viscosity index improvers provide lubricants with high and
low temperature operability. These additives impart shear stability
at elevated temperatures and acceptable viscosity at low
temperatures.
[0083] Suitable viscosity index improvers include high molecular
weight hydrocarbons, polyesters and viscosity index improver
dispersants that function as both a viscosity index improver and a
dispersant. Typical molecular weights of these polymers are between
10,000 to 1,500,000, more typically 20,000 to 1,200,000, and even
more typically between 50,000 and 1,000,000.
[0084] Examples of suitable viscosity index improvers are linear or
star-shaped polymers and copolymers of methacrylate, butadiene,
olefins, or alkylated styrenes. Polyisobutylene is a commonly used
viscosity index improver. Another suitable viscosity index improver
is polymethaerylate (copolymers of various chain length alkyl
methacrylates, for example), some formulations of which also serve
as pour point depressants. Other suitable viscosity index improvers
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.
[0085] 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". Polyisoprene polymers are
commercially available from Infineum International Limited, e.g.
under the trade designation "SV200"; diene-styrene copolymers are
commercially available from Infineum International Limited, e.g.
under the trade designation "SV 260".
[0086] In an embodiment of this disclosure, the viscosity index
improvers may be used in an amount of less than 2.0 weight percent,
preferably less than 1.0 weight percent, and more preferably less
than 0.5 weight percent, based on the total weight of the
formulated oil or lubricating engine oil.
[0087] In another embodiment of this disclosure, the viscosity
index improvers may be used in an amount of from 0.25 to 2.0 weight
percent, preferably 0.15 to 1.0 weight percent, and more preferably
0.05 to 0.5 weight percent, based on the total weight of the
formulated oil or lubricating engine oil.
Detergents
[0088] Illustrative detergents useful in this disclosure include,
for example, alkali metal detergents, alkaline earth metal
detergents, or mixtures of one or more alkali metal in 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 acid, carboxylic acid, phosphorous acid, phenol, or
mixtures thereof. The counterion is typically an alkaline earth or
alkali metal.
[0089] 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.
[0090] 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.7, 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.
[0091] Metal salts of carboxylic acids are also useful as
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
##STR00001##
where R is an alkyl group having 1 to 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, or barium. More preferably, M is calcium.
[0092] 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.
[0093] Alkaline earth metal phosphates are also used as detergents
and are known in the art.
[0094] 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.
[0095] Preferred detergents include calcium phenates, calcium
sulfonates, calcium salicylates, magnesium phenates, magnesium
sulfonates, magnesium salicylates and other related components
(including borated detergents), and mixtures thereof. Preferred
detergents include magnesium sulfonate and calcium salicylate.
[0096] The detergent concentration in the lubricating oils of this
disclosure can range from 1.0 to 6.0 weight percent, preferably 2.0
to 5.0 weight percent, and more preferably from 2.0 weight percent
to 4.0 weight percent, based on the total weight of the lubricating
oil.
[0097] 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 20 weight percent to 80 weight percent, or from 40 is weight
percent to 60 weight percent, of active detergent in the "as
delivered" detergent product.
Dispersants
[0098] 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 above form ash upon combustion.
[0099] 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.
[0100] Chemically, many dispersants may be characterized as
phenates, sulfonates, sulfurized phenates, salicylates,
naphthenates, stearates, carbamates, thiocarbamates, phosphorus
derivatives. A particularly useful class of dispersants are the
alkenylsuccinic derivatives, typically produced by the reaction of
a long chain hydrocarbyl substituted succinic compound, usually a
hydrocarbyl substituted succinic anhydride, with a polydroxyl 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.
[0101] 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.
[0102] 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 1:1 to 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.
[0103] 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.
[0104] 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.
[0105] 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 0.1 to 5 moles of boron
per mole of dispersant reaction product.
[0106] 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.
[0107] 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 NH.RTM..sub.2 group-containing reactants.
[0108] 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.
[0109] 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
500 to 5000 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. Such additives may be used in an amount of 0.1 to 20
weight percent, preferably 0.5 to 8 weight percent.
[0110] 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 20 weight percent to 80 weight percent, or
from 40 weight percent to 60 weight percent, of active dispersant
in the "as delivered" dispersant product.
Antioxidants
[0111] 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.
[0112] 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-6t-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'-methytene-bis(2,6-di-t-butyl phenol).
[0113] 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 aralkyiene 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
20 carbon atoms, and preferably contains from 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
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.
[0114] Typical aromatic amines antioxidants have alkyl substituent
groups of at least 6 carbon atoms. Examples of aliphatic groups
include hexyl, heptyl, octyl, nonyl, and decyl. Generally, the
aliphatic groups will not contain more than 14 carbon atoms. The
general types of amine antioxidants useful in the present
compositions include diphenylamines, phenyl naphthylamines,
phenothiazines, imidodibenzyles and diphenyl phenylene diamines.
Mixtures of two or more aromatic amities are also useful. Polymeric
amine antioxidants can also be used. Particular examples of
aromatic amine antioxidants useful in the present disclosure
include: p,p'-dioctyidiphenylamine;
t-octylphenyl-alpha-naphthylamine; phenyl-alphanaphthylamine; and
p-octylphenyl-alpha-naphthylamine.
[0115] Sulfurized alkyl phenols and alkali or alkaline earth metal
salts thereof also are useful antioxidants.
[0116] 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 0.01 to 5 weight percent, preferably 0.01 to 1.5 weight
percent, more preferably zero to less than 1.5 weight percent, most
preferably zero.
Pour Point Depressants (PPDs)
[0117] 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 0.01 to 5 weight percent, preferably 0.01 to
11.5 weight percent.
Seal Compatibility Agents
[0118] 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 0.01
to 3 weight percent, preferably 0.01 to 2 weight percent.
Antifoam Agents
[0119] 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.
Friction Modifiers
[0120] 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, 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 tube
compositions of this disclosure. Friction modifiers may include
metal-containing compounds or materials as well as ashless
compounds or materials, or mixtures thereof. Metal-containing
friction modifiers may include metal salts or metalligand 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, 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; and WO 98/26030.
[0121] Ashless friction modifiers may also 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 O, 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 is acids, fatty alcohols, fatty
amides, fatty esters, hydroxyl-containing carboxylates, and
comparable synthetic long-chain hydrocarbyl acids, alcohols,
amides, esters, carboxylates, and the like. In some instances fatty
organic acids, fatty amines, and sulfurized fatty acids may be used
as suitable friction modifiers.
[0122] Useful concentrations of friction modifiers may range from
0.01 weight percent to 10-15 weight percent or more, often with a
preferred range of 0.1 weight percent to 5 weight percent.
Concentrations of molybdenum-containing materials are often
described in terms of Mo metal concentration. Advantageous
concentrations of Mo may range from 10 ppm to 3000 ppm or more, and
often with a preferred range of 20-2000 ppm, and in some instances
a more preferred range of 30-1000 ppm. Friction modifiers of all
types may be used alone or in mixtures with the materials of this
disclosure. Often mixtures of two or more friction modifiers, or
mixtures of friction modifier(s) with alternate surface active
material(s), are also desirable.
[0123] 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.
[0124] 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 0.01 to 5 weight percent, preferably 0.01
to 1.5 weight percent.
[0125] 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 I below.
[0126] 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) Dispersant 0.1-20 0.1-8 Detergent 0.1-20 0.1-8 Friction
Modifier 0.01-5 0.01-1.5 Antioxidant 0.1-5 0.1-1.5 Pour Point
Depressant 0.0-5 0.01-1.5 (PPD) Anti-foam Agent 0.001-3 0.001-0.15
Viscosity Index Improver 0.1-2 0.1-1 (solid polymer basis)
Anti-wear 0.4-1.2 0.5-1 Inhibitor and Antirust 0.01-5 0.01-1.5
[0127] 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.
[0128] The following non-limiting examples are provided to
illustrate the disclosure.
EXAMPLES
[0129] PCMO (passenger car motor oil) formulations were prepared.
FIG. 1 provides formulation details in weight percent based on the
total weight percent of the formulation. The alkoxylated alcohol
used in each of the formulations in FIG. 1 was a polyoxyalkylene
alkyl ether. The Group III base stock used in each of the
formulations in FIG. 1 was Yubase.TM. 4 Plus. The Group IV base
stock used in each of the formulations in FIG. 1 was a mixture of
PAO 4 and PAO 6. The Group V base stock used in each of the
formulations in FIG. 1 was ExxonMobil Chemical MCP 2481. The
viscosity modifier used in each of the formulations in FIG. 1 was
Lubrizol VL1151J. The additive package used in each of the
formulations in FIG. 1 included the following: detergents,
dispersants, antioxidants, antiwear additives, defoamant, ashless
friction modifier, MoDTC, and a pour point depressant. All of the
ingredients are commercially available.
[0130] Bench and engine testing was conducted for each of the
formulations listed in FIG. 1. The testing results are set forth in
FIG. 2. The bench testing in FIG. 2 included the following:
kinematic viscosity (KV) at 100.degree. C. measured by ASTM D445;
high temperature high shear (HTHS) viscosity at 150.degree. C.
measured by ASTM D4683; and cold cranking simulator (CCS) at
-35.degree. C. measured by ASTM D5273. The engine testing in FIG. 2
included the following: Sequence IIIG (kinematic viscosity increase
at 40.degree. C., %) measured by ASTM D7320; Sequence IIIG (average
weighted piston deposits, merits) measured by ASTM D7320; Sequence
IIIG (average cam and lifter wear, .mu.m) measured by ASTM D7320;
oil consumption (L) measured by ASTM D7320; Sequence VID FEI 1
(Fuel Economy Improvement 1) measured by ASTM D7589; Sequence VID
FEI 2 (Fuel Economy Improvement 2) measured by ASTM D7589; and
Sequence VID FEI SUM (Fuel Economy Improvement SUM) measured by
ASTM D7589.
[0131] In FIG. 2, a comparison of the Reference 1 formulation and
Example 3 formulation shows that addition of alkoxylated alcohol
delivers improved high temperature deposit control while
maintaining good wear protection as measured by the Sequence IIIG
test. Moreover, using the Sequence VID test as a measure of fuel
economy, a comparison of the Reference 2 formulation and Example 3
formulation shows that addition of alkoxylated alcohol also
significantly improves fuel economy. The fuel economy benefit was
observed with the Example 3 formulation having the alkoxylated
alcohol even though this formulation was a heavier viscosity grade
(5 W-20) than the Reference 2 formulation (0 W-20).
[0132] MTM (mini-traction machine) data for the formulation of
Example 3 as shown in FIG. 3 indicates a high level of alkoxylated
alcohol activity at low temperature (<100.degree. C.) as
compared to the formulation of Reference 1. At a temperature of
50.degree. C., the presence of the alkoxylated alcohol maintains a
low coefficient of friction over many test cycles. In contrast, the
formulation without the alkoxylated alcohol (Reference 1) exhibits
an increase in friction as the number of test cycles increases.
Additionally, FIG. 4 indicates alkoxylated alcohol activity even at
higher temperature suggesting preferential adsorption of the
alkoxylated alcohol onto the steel surface. At 100.degree. C., the
presence of the alkoxylated alcohol significantly reduced friction
over a broad range of sliding speed (1000 mm/s to 10 mm/s).
[0133] PCMO (passenger car motor oil) formulations were prepared.
FIG. 5 provides formulation details in weight percent based on the
total weight percent of the formulation. The alkoxylated alcohol
used in formulation 6 in FIG. 5 was a polyoxyalkylene alkyl ether.
The styrene-isoprene block copolymers used in each of the
formulations in FIG. 5 was Infineum.TM. SV140, The Group II base
stock used in each of the formulations in FIG. 5 was Exxon Mobil
EHC 45. The Group IV base stock used in each of the formulations in
FIG. 5 was a mixture of PAO 4 and PAO 6. The C.sub.8/C.sub.10
trimethylolpropane (TMP) used in each of the formulations in FIG. 5
was ExxonMobil Chemical MCP 166. The additive package used in each
of the formulations in FIG. 5 included the following: detergents,
dispersants, antioxidants, antiwear additives, defoamant, ashless
friction modifier, MoDTC, and a pour point depressant. All of the
ingredients are commercially available.
[0134] The engine testing in FIG. 5 included the following:
Sequence IIIG (kinematic viscosity increase at 40.degree. C., %)
measured by ASTM D7320; Sequence IIIG (average weighted piston
deposits, merits) measured by ASTM D7320; Sequence IIIG (hot stuck
rings) measured by ASTM D7320, Sequence IIIG (average cam and
lifter wear, .mu.m) measured by ASTM D7320; Sequence IIIG (oil ring
land deposit, merits) measured by ASTM D7320; Sequence IIIG
(undercrown, merits) measured by ASTM D7320, Sequence IIIG (Groove
1) measured by ASTM D7320; Sequence IIIG (Groove 2) measured by
ASTM 1)7320; Sequence IIIG (Groove 3) measured by ASTM D7320;
Sequence IIIG (Land 2) measured by ASTM D7320; Sequence IIIG (oil
consumption, L) measured by ASTM D7320; and Sequence IIIG
(phosphorus retention, %) as measured by ASTM D7320.
[0135] As shown in FIG. 5, the addition of 5% of the alkoxylated
alcohol provided benefits in overall piston cleanliness (weighted
piston deposits) with clear benefits observed in the following
regions of the piston: oil ring land (ORLD), groove 2, and land
2.In addition, the alkoxylated alcohol surprisingly reduced wear by
45% which is expected to significantly improve vehicle durability.
Also, the addition of the alkoxylated alcohol unexpectedly improved
phosphorus retention which is expected to result in less phosphorus
poisoning catalytic converters and result in improved emissions
control.
[0136] Additional PCMO (passenger car motor oil) formulations were
prepared. FIG. 6 provides formulation details in weight percent
based on the total weight percent of the formulation. The Group V
base stock used in each of the formulations in FIG. 6 was
ExxonMobil Chemical MCP 2481. The Group IIIA base stock used in
reference formulation 5 and formulations 7 and 8 in FIG. 6 was
Visom 4. The Group IIIB base stock used in reference formulations 1
and 4 in FIG. 6 was Yubase.TM. 4 Plus. The Group IV base stock used
in each of the formulations in FIG. 6 was a mixture of PAO 4 and
PAO 6. The Detergent 5 used in each of the formulations in FIG. 6
was Infineum P5090. The Detergent 6 used in reference formulations
1 and 4 in FIG. 6 was Parabar 9340. The Detergent 3 used in
formulations 7 and 8 in FIG. 6 was Infineum M7102. The Alkoxylated
Alcohol FM1 used in formulations 7 and 8 in FIG. 6 was a
polyoxyalkylene alkyl ether. The Organic FM2 used in each of the
formulations in FIG. 6 was Perfad FM 3336. The Organometallic FM3
used in each of the formulations in FIG. 6 was MolyVan 855. The
Organometallic FM4 used in each of the formulations in FIG. 6 was
Infineum C9455. The additive package used in each of the
formulations in FIG. 6 included the following: detergents,
dispersants, antioxidants, antiwear additives, defoamant, ashless
friction modifier, MoDTC, and a pour point depressant. Dispersants
can include borated and non-borated molecules derived from high
terminal vinylic polyisobutylene of molecular weight greater than
2500 which are reacted with maleic anhydride and the like, such as
C9280. All of the ingredients are commercially available.
[0137] Bench and engine testing was conducted for each of the
formulations listed in FIG. 6. The testing results are set forth in
FIG. 6. The engine testing in FIG. 6 included the following:
Sequence IIIG (WPD) measured by ASTM D7320; Sequence IIIG
(viscosity increase, %) measured by ASTM D7320; Sequence IIIG
(wear, microns) measured by ASTM D7320; Sequence IIIG (oil
consumption, L) measured by ASTM D7320; Sequence VID (FEI 1)
measured by ASTM D7589; Sequence VID (FEI 2) measured by ASTM
D7589; and Sequence VID (FEI SUM) measured by ASTM D7589. The bench
testing in FIG. 6 included the following: kinematic viscosity (KV)
at 100.degree. C. measured by ASTM D445; high temperature high
shear (HTFIS) viscosity at 150.degree. C. measured by ASTM D4683;
and MTM friction average measured by WI307SF-9.
[0138] As shown in FIG. 6, the addition of the alkoxylated alcohol
provided good wear protection as measured by the Sequence IIIG
test. Moreover, using the Sequence VID test as a measure of fuel
economy, the addition of the alkoxylated alcohol shows
significantly improved fuel economy. The data in FIG. 6 shows both
improved fuel economy and piston cleanliness for Example 7 and 8
formulations in comparison to the Reference 1, 4 and 5
formulations. As shown in FIG. 6, the addition of 0.3 to 1.0% of
the alkoxylated alcohol provided benefits in overall piston
cleanliness (weighted piston deposits) with clear benefits observed
in the following regions of the piston: oil ring land (ORLD),
groove 2, and land 2. In addition of the alkoxylated alcohol
unexpectedly improved phosphorus retention which is expected to
result in less phosphorus poisoning catalytic converters and result
in improved emissions control.
[0139] Additional PCMO (passenger car motor oil) formulations were
prepared. FIG. 7 provides formulation details in weight percent
based on the total weight percent of the formulation. The Group V
base stock used in each of the formulations in FIG. 7 was
ExxonMobil Chemical MCP 2481. The Group III base stock used in each
of the formulations in FIG. 7 was Yubase.TM. 4 Plus. The Group IV
base stock used in each of the formulations in FIG. 7 was a mixture
of PAO 4 and PAO 6. The alkoxylated alcohol used in each of the
formulations in FIG. 7 was a polyoxyalkylene alkyl ether. The
viscosity modifier used in each of the formulations in FIG. 7 was
Lubrizol VL1151J. The additive package used in each of the
formulations in FIG. 7 included the following: detergents,
dispersants, antioxidants, antiwear additives, defoamant, ashless
friction modifier, MoDTC, and a pour point depressant. All of the
ingredients are commercially available.
[0140] Bench and engine testing was conducted for each of the
formulations listed in FIG. 7. The testing results are set forth in
FIG. 7. The bench testing in FIG. 7 included the following:
sulfated ash as measured by ASTM D874; total base number (TBN) as
measured by ASTM D2896; kinematic viscosity (KV) at 100.degree. C.
measured by ASTM D445; high temperature high shear (HTHS) viscosity
at 150.degree. C. measured by ASTM D4683; and cold cranking
simulator (CCS) at -35.degree. C. measured by ASTM D5273.
[0141] As shown in FIG. 7, Example 9 contains a sulfated ash level
of 1.8 weight percent and a total base number of 15. Example 10
contains a sulfated ash level of 0.3 weight percent and a total
base number of 4. Low total base number can be preferred in
combination with alkoxylated alcohols. Low sulfated ash can be
preferred in combination with alkoxylated alcohols.
[0142] The lubricating engine oil formulations in FIG. 8 are
combinations of additives and base stocks and are anticipated to
have a kinematic viscosity at 100.degree. C. around 7 cSt and high
temperature high shear (10.sup.-6 s.sup.-1) viscosity at
150.degree. C. around 2.3 el). The lubricating engine oil
formulations of Examples 11, 12, 15, 16, 19, and 20 are anticipated
to have a phosphorus level around 300 ppm. The lubricating engine
oil formulations of Examples 13, 14, 17, 18, 21, 22 are anticipated
to have a phosphorus level around 700 ppm. The lubricating engine
oil formulations of Examples 20 and 22 are anticipated to have a
sulfated ash level around 0.3 weight percent and a total base
number around 4. The lubricating engine oil formulations of
Examples 11-19 and 21 are anticipated to have sulfated ash levels
greater than or equal to 1.0 weight percent and total base number
greater than or equal to 9. The lubricating engine oil formulations
of Examples 15 and 17 do not contain molybdenum. The lubricating
engine oil formulations of Examples 16 and 18 are anticipated to
have a molybdenum level of around 250 ppm. The lubricating engine
oil formulations of Examples 11-15 and 19-22 are anticipated to
have molybdenum levels of around 90 ppm. All lubricating engine oil
formulations in FIG. 8 that include at least one alkoxylated
alcohol are anticipated to provide improvements in fuel economy
without sacrificing engine durability (e.g., while maintaining or
improving high temperature wear, deposit and varnish control) in an
engine lubricated with the lubricating oil formulation.
[0143] The lubricating engine oil formulations in FIG. 9 are
combinations of additives and base stocks and are anticipated to
have a kinematic viscosity at 100.degree. C. around 6 cSt and high
temperature high shear (10.sup.-6 s.sup.-1) viscosity at
150.degree. C. around 2.0 cP. The lubricating engine oil
formulations of Examples 23, 24, 27, 28, 31, and 32 are anticipated
to have a phosphorus level around 300 ppm. The lubricating engine
oil formulations of Examples 25, 26, 29, 30, 33, and 34 are
anticipated to have a phosphorus level around 700 ppm. The
lubricating engine oil formulations of Examples 32 and 34 are
anticipated to have a sulfated ash level around 0.3 weight percent
and a total base number around 4. The lubricating engine oil
formulations of Examples 23-31 and 33 are anticipated to have
sulfated ash levels greater than or equal to 1.0 weight percent and
total base number greater than or equal to 9. The lubricating
engine oil formulations of Examples 27 and 29 do not contain
molybdenum. The lubricating engine oil formulations of Examples 28
and 30 are anticipated to have a molybdenum level of around 250
ppm. The lubricating engine oil formulations of Examples 23-27 and
31-34 are anticipated to have molybdenum levels of around 90 ppm.
All lubricating engine oil formulations in FIG. 9 that include at
least one alkoxylated alcohol are anticipated to provide
improvements in fuel economy without sacrificing engine durability
(e.g., while maintaining or improving high temperature wear,
deposit and varnish control) in an engine lubricated with the
lubricating oil formulation.
[0144] The lubricating engine oil formulations in FIG. 10 are
combinations of additives and base stocks and are anticipated to
have a kinematic viscosity at 100.degree. C. around 8 cSt and high
temperature high shear (10.sup.-6 s.sup.-1) viscosity at
150.degree. C. around 2.7 cP. The lubricating engine oil
formulations of Examples 35, 36, 39, 40, 43, and 44 are anticipated
to have a phosphorus level around 300 ppm. The lubricating engine
oil formulations of Examples 37, 38, 41, 42, 45, and 46 are
anticipated to have a phosphorus level around 700 ppm. The
lubricating engine oil formulations of Examples 44 and 46 are
anticipated to have a sulfated ash level around 0.3 weight percent
and a total base number around 4. The lubricating engine oil
formulations of Examples 35-43 and 45 are anticipated to have
sulfated ash levels greater than or equal to 1.0 weight percent and
total base number greater than or equal to 9. The lubricating
engine oil formulations of Examples 39 and 41 do not contain
molybdenum. The lubricating engine oil formulations of Examples 40
and 42 are anticipated to have a molybdenum level of around 250
ppm. The lubricating engine oil formulations of Examples 35-39 and
43-46 are anticipated to have molybdenum levels of around 90 ppm.
All lubricating engine oil formulations in FIG. 10 that include at
least one alkoxylated alcohol are anticipated to provide
improvements in fuel economy without sacrificing engine durability
(e.g., while maintaining or improving high temperature wear,
deposit and varnish control) in an engine lubricated with the
lubricating oil formulation.
[0145] The lubricating engine oil formulations in FIG. 11 are
combinations of additives and base stocks and are anticipated to
have a kinematic viscosity at 100.degree. C. around 10 cSt and high
temperature high shear (10.sup.-6 s.sup.-1) viscosity at
150.degree. C. around 3.0 cP. The lubricating engine oil
formulations of Examples 47, 48, 51, 52, 55, and 56 are anticipated
to have a phosphorus level around 300 ppm. The lubricating engine
oil formulations of Examples 49, 50, 53, 54, 57, and 58 are
anticipated to have a phosphorus level around 700 ppm. The
lubricating engine oil formulations of Examples 56 and 58 are
anticipated to have a sulfated ash level around 0.3 weight percent
and a total base is number around 4. The lubricating engine oil
formulations of Examples 47-55 and 57 are anticipated to have
sulfated ash levels greater than or equal to 1.0 weight percent and
total base number greater than or equal to 9. The lubricating
engine oil formulations of Examples 51 and 53 do not contain
molybdenum. The lubricating engine oil formulations of Examples 52
and 54 are anticipated to have a molybdenum level of around 250
ppm. The lubricating engine oil formulations of Examples 47-51 and
55-58 are anticipated to have molybdenum levels of around 90 ppm.
All lubricating engine oil formulations in FIG. 11 that include at
least one alkoxylated alcohol are anticipated to provide
improvements in fuel economy without sacrificing engine durability
(e.g., while maintaining or improving high temperature wear,
deposit and varnish control) in an engine lubricated with the
lubricating oil formulation.
[0146] 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.
[0147] 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 to skilled
in the art to which the disclosure pertains.
[0148] 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.
* * * * *