U.S. patent application number 17/122221 was filed with the patent office on 2021-06-24 for lubricating oil compositions and methods of use.
The applicant listed for this patent is ExxonMobil Research and Engineering Company. Invention is credited to David G.L. Holt, David A. Racke, Lin Wang.
Application Number | 20210189282 17/122221 |
Document ID | / |
Family ID | 1000005322985 |
Filed Date | 2021-06-24 |
United States Patent
Application |
20210189282 |
Kind Code |
A1 |
Wang; Lin ; et al. |
June 24, 2021 |
LUBRICATING OIL COMPOSITIONS AND METHODS OF USE
Abstract
This disclosure relates to a method for improving air release in
a lubricating oil. The method involves formulating a composition
having at least one lubricating oil base stock as a major
component, and one or more lubricating oil additives, as a minor
component. The one or more lubricating oil additives include at
least one polyalkylene glycol. The at least one polyalkylene glycol
is soluble in the at least one lubricating oil base stock. The
weight ratio of the at least one polyalkylene glycol to the at
least one lubricating oil base stock is from about 1:99 to about
7:93. During operation of a lubricating system containing the
lubricating oil, release of entrained air in the lubricating oil is
improved, as determined by ASTM D-3427-15, as compared to release
of entrained air achieved using a lubricating oil containing other
than the at least one polyalkylene glycol. This disclosure also
relates to lubricating oils having at least one oil soluble
polyalkylene glycol (OSP).
Inventors: |
Wang; Lin; (Furlong, PA)
; Holt; David G.L.; (Center Valley, PA) ; Racke;
David A.; (West Deptford, NJ) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ExxonMobil Research and Engineering Company |
Annandale |
NJ |
US |
|
|
Family ID: |
1000005322985 |
Appl. No.: |
17/122221 |
Filed: |
December 15, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62949628 |
Dec 18, 2019 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C10N 2030/18 20130101;
C10N 2020/02 20130101; C10N 2030/02 20130101; C10M 111/04 20130101;
C10N 2020/04 20130101; C10M 2209/1075 20130101; C10M 145/34
20130101 |
International
Class: |
C10M 145/34 20060101
C10M145/34; C10M 111/04 20060101 C10M111/04 |
Claims
1. A lubricating oil having a composition comprising: at least one
lubricating oil base stock as a major component, and one or more
lubricating oil additives, as a minor component; wherein the one or
more lubricating oil additives comprise at least one polyalkylene
glycol, and is other than a sulfurized olefin; wherein the at least
one polyalkylene glycol is soluble in the at least one lubricating
oil base stock; wherein the weight ratio of the at least one
polyalkylene glycol to the at least one lubricating oil base stock
is from about 1:99 to about 7:93; wherein, during operation of a
lubricating system containing the lubricating oil, release of
entrained air in the lubricating oil is improved, as determined by
ASTM D-3427-15, as compared to release of entrained air achieved
using a lubricating oil containing other than the at least one
polyalkylene glycol.
2. The lubricating oil of claim 1 wherein, during operation of a
lubricating system containing the lubricating oil, the time
required for entrained air content to fall to 0.2 volume percent,
as determined by ASTM D-3427-15, is reduced at least 5%, as
compared to the time required for entrained air content to fall to
0.2 volume percent, using a lubricating oil containing other than
the at least one polyalkylene glycol.
3. The lubricating oil of claim 1 wherein, during operation of a
lubricating system containing the lubricating oil, the time
required for entrained air content to fall to 0.2 volume percent,
as determined by ASTM D-3427-15, is reduced at least 10%, as
compared to the time required for entrained air content to fall to
0.2 volume percent, using a lubricating oil containing other than
the at least one polyalkylene glycol.
4. The lubricating oil of claim 1 wherein the weight ratio of the
at least one polyalkylene glycol to the at least one lubricating
oil base stock is from about 1:99 to about 6.5:93.5.
5. The lubricating oil of claim 1 wherein the weight ratio of the
at least one polyalkylene glycol to the at least one lubricating
oil base stock is from about 1:99 to about 4.5:95.5.
6. The lubricating oil of claim 1 wherein the at least one
polyalkylene glycol comprises from about 25 to about 75 weight
percent units derived from butylene oxide and from about 25 to
about 75 weight percent units derived from propylene oxide,
initiated by one or more initiators selected from monols, diols and
polyols.
7. The lubricating oil of claim 1 wherein the at least one
polyalkylene glycol comprises from about 45 to about 55 weight
percent units derived from butylene oxide and about 45 to about 55
weight percent units derived from propylene oxide, initiated by one
or more monol initiators.
8. The lubricating oil of claim 1 wherein the at least one
polyalkylene glycol is selected from the group consisting of
copolymers comprising units derived from propylene oxide and
butylene oxide, polybutylene oxide homopolymer, and combinations
thereof.
9. The lubricating oil of claim 1 wherein the at least one
polyalkylene glycol has a kinematic viscosity (KV.sub.40) from
about 15 to about 100 cSt at 40.degree. C. as determined by ASTM
D-445-19, and a molecular weight from about 400 to about 1100
grams/mole.
10. The lubricating oil of claim 1 wherein the lubricating oil base
stock comprises a Group I, Group II, Group III, Group IV or Group V
base oil.
11. The lubricating oil of claim 1 wherein the lubricating oil base
stock is present in an amount of from about 75 weight percent to
about 95 weight percent, and the at least one polyalkylene glycol
is present in an amount from about 1 to about 7 weight percent,
based on the total weight of the lubricating oil.
12. The lubricating oil of claim 1 wherein the one or more
lubricating oil additives further comprise one or more of an
antiwear additive, viscosity modifier, antioxidant, detergent,
dispersant, pour point depressant, corrosion inhibitor, metal
deactivator, seal compatibility additive, antifoam agent,
inhibitor, friction modifier, and anti-rust additive.
13. A method for improving air release in a lubricating oil, said
method comprising: formulating a composition comprising at least
one lubricating oil base stock as a major component, and one or
more lubricating oil additives, as a minor component; wherein the
one or more lubricating oil additives comprise at least one
polyalkylene glycol, and is other than a sulfurized olefin; wherein
the at least one polyalkylene glycol is soluble in the at least one
lubricating oil base stock; wherein the weight ratio of the at
least one polyalkylene glycol to the at least one lubricating oil
base stock is from about 1:99 to about 7:93; wherein, during
operation of a lubricating system containing the lubricating oil,
release of entrained air in the lubricating oil is improved, as
determined by ASTM D-3427-15, as compared to release of entrained
air achieved using a lubricating oil containing other than the at
least one polyalkylene glycol.
14. The method of claim 13 wherein, during operation of a
lubricating system containing the lubricating oil, the time
required for entrained air content to fall to 0.2 volume percent,
as determined by ASTM D-3427-15, is reduced at least 5%, as
compared to the time required for entrained air content to fall to
0.2 volume percent, using a lubricating oil containing other than
the at least one polyalkylene glycol.
15. The method of claim 13 wherein, during operation of a
lubricating system containing the lubricating oil, the time
required for entrained air content to fall to 0.2 volume percent,
as determined by ASTM D-3427-15, is reduced at least 10%, as
compared to the time required for entrained air content to fall to
0.2 volume percent, using a lubricating oil containing other than
the at least one polyalkylene glycol.
16. The method of claim 13 wherein the weight ratio of the at least
one polyalkylene glycol to the at least one lubricating oil base
stock is from about 1:99 to about 6.5:93.5
17. The method of claim 13 wherein the weight ratio of the at least
one polyalkylene glycol to the at least one lubricating oil base
stock is from about 1:99 to about 4.5:95.5
18. The method of claim 13 wherein the at least one polyalkylene
glycol comprises from about 25 to about 75 weight percent units
derived from butylene oxide and from about 25 to about 75 weight
percent units derived from propylene oxide, initiated by one or
more initiators selected from monols, diols and polyols.
19. The method of claim 13 wherein the at least one polyalkylene
glycol comprises from about 45 to about 55 weight percent units
derived from butylene oxide and about 45 to about 55 weight percent
units derived from propylene oxide, initiated by one or more monol
initiators.
20. The method of claim 13 wherein the at least one polyalkylene
glycol is selected from the group consisting of copolymers
comprising units derived from propylene oxide and butylene oxide,
polybutylene oxide homopolymer, and combinations thereof.
21. The method of claim 13 wherein the at least one polyalkylene
glycol has a kinematic viscosity (KV.sub.40) from about 15 to about
100 cSt at 40.degree. C. as determined by ASTM D-445-19, and a
molecular weight from about 400 to about 1100 grams/mole.
22. The method of claim 13 wherein the lubricating oil base stock
comprises a Group I, Group II, Group III, Group IV or Group V base
oil.
23. The method of claim 13 wherein the lubricating oil base stock
is present in an amount of from about 75 weight percent to about 95
weight percent, and the at least one polyalkylene glycol is present
in an amount from about 1 to about 7 weight percent, based on the
total weight of the lubricating oil.
24. The method of claim 13 wherein the one or more lubricating oil
additives further comprise one or more of an antiwear additive,
viscosity modifier, antioxidant, detergent, dispersant, pour point
depressant, corrosion inhibitor, metal deactivator, seal
compatibility additive, antifoam agent, inhibitor, friction
modifier, and anti-rust additive.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application No. 62/949,628, filed on Dec. 18, 2019, the entire
contents of which are incorporated herein by reference.
FIELD
[0002] This disclosure relates to lubricating oils having an oil
soluble polyalkylene glycol (OSP) additive. This disclosure also
relates to methods for improving air release, as determined by ASTM
D-3427-15, in lubricating oils used in lubricating systems.
BACKGROUND
[0003] The art of formulating lubricating oil compositions has
become more complex as a result of increased government and user
environmental standards and increased user performance
requirements. Air release is very important in lubricants
particularly industrial lubricants. Lubricants which release
entrained air faster will exhibit performance benefits versus
fluids which release air more slowly.
[0004] Recently, equipment manufacturers are requiring improved air
release properties at many different viscosity grades. All
lubricating oil systems contain some air. It can be found in four
phases: free air, dissolved air, entrained air and foam. Free air
is trapped in a system, such as an air pocket in a hydraulic line.
Dissolved air is in solution with the oil and is not visible to the
naked eye. Foam is a collection of closely packed bubbles
surrounded by thin films of oil that collect on the surface of the
oil.
[0005] Air entrainment is a small amount of air in the form of
extremely small bubbles (generally less than 1 mm in diameter)
dispersed throughout the bulk of the oil. Agitation of lubricating
oil with air in equipment, such as bearings, couplings, gears,
pumps, and oil return lines, may produce a dispersion of finely
divided air bubbles in the oil. If the residence time in the
reservoir is too short to allow the air bubbles to rise to the oil
surface, a mixture of air and oil will circulate through the
lubricating oil system. This may result in an inability to maintain
oil pressure (particularly with centrifugal pumps), incomplete oil
films in bearings and gears, and poor hydraulic system performance
or failure. Air entrainment is treated differently than foam, and
is most often a completely separate problem. A partial list of
potential effects of air entrainment include: pump cavitation,
spongy, erratic operation of hydraulics, loss of precision control,
vibrations, oil oxidation, component wear due to reduced lubricant
viscosity, equipment shut down when low oil pressure switches trip,
"micro-dieseling" due to ignition of the bubble sheath at the high
temperatures generated by compressed air bubbles, safety problems
in turbines if overspeed devices do not react quickly enough, and
loss of head in centrifugal pumps.
[0006] Antifoamants, including but not limited to silicone
additives, produce smaller bubbles in the bulk of the oil as an
unintended consequence of their use. In stagnant systems, the
combination of smaller bubbles and greater sheath density can cause
serious air entrainment problems.
[0007] Casual exposure to silicone can have a significant effect on
the lubricant. There are reports of air entrainment resulting from
oil passing through hoses that had been formed on a silicone-coated
mandrel. Other known causes of entrainment problems include
contaminants, overadditizing and reservoir design.
[0008] One commonly used method to measure air release properties
of petroleum oils is ASTM D 3427. This test method measures air
content via density at given time intervals following aeration at
temperatures specified by viscosity grade. Air release performance
is reported either in air content at various time intervals or the
time required for the air entrained in the oil to reduce in volume
to either 0.1% or 0.2% is recorded as the air release time.
[0009] Most solutions to the air entrainment problem have been to
redesign lubricating oil systems or choose additives not likely to
cause aeration issues. There is a need to create new understanding
of additives to achieve favorable air release properties and reduce
aeration issues. Accordingly, this disclosure satisfies that
need.
SUMMARY
[0010] This disclosure relates to lubricating oils having an oil
soluble polyalkylene glycol (OSP) additive. This disclosure also
relates to methods for improving air release, as determined by ASTM
D-3427-15, in lubricating oils used in lubricating systems.
[0011] This disclosure relates in part to a lubricating oil having
a composition having at least one lubricating oil base stock as a
major component, and one or more lubricating oil additives, as a
minor component. The one or more lubricating oil additives include
at least one polyalkylene glycol. The at least one polyalkylene
glycol is soluble in the at least one lubricating oil base stock.
The one or more lubricating oil additives is other than a
sulfurized olefin. The weight ratio of the at least one
polyalkylene glycol to the at least one lubricating oil base stock
is from about 1:99 to about 7:93. During operation of a lubricating
system containing the lubricating oil, release of entrained air in
the lubricating oil is improved, as determined by ASTM D-3427-15,
as compared to release of entrained air achieved using a
lubricating oil containing other than the at least one polyalkylene
glycol.
[0012] This disclosure also relates in part to a method for
improving air release in a lubricating oil. The method involves
formulating a composition comprising at least one lubricating oil
base stock as a major component, and one or more lubricating oil
additives, as a minor component. The one or more lubricating oil
additives include at least one polyalkylene glycol. The at least
one polyalkylene glycol is soluble in the at least one lubricating
oil base stock. The one or more lubricating oil additives is other
than a sulfurized olefin. The weight ratio of the at least one
polyalkylene glycol to the at least one lubricating oil base stock
is from about 1:99 to about 7:93. During operation of a lubricating
system containing the lubricating oil, release of entrained air in
the lubricating oil is improved, as determined by ASTM D-3427-15,
as compared to release of entrained air achieved using a
lubricating oil containing other than the at least one polyalkylene
glycol.
[0013] It has been surprisingly found that, in accordance with this
disclosure, during operation of a lubricating system containing the
lubricating oil of this disclosure, the time required for entrained
air content to fall to 0.2 volume percent, as determined by ASTM
D-3427-15, is reduced at least 5%, as compared to the time required
for entrained air content to fall to 0.2 volume percent using a
lubricating oil containing other than the at least one polyalkylene
glycol.
[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 lubricating oil formulations and testing
results, namely, air release testing results as determined by ASTM
D-3427-15, in accordance with the Examples.
DETAILED DESCRIPTION
Definitions
[0016] "About" or "approximately." All numerical values within the
detailed description and the claims herein are modified by "about"
or "approximately" the indicated value, and take into account
experimental error and variations that would be expected by a
person having ordinary skill in the art.
[0017] "Major amount" as it relates to components included within
the lubricating oils of the specification and the claims means
greater than or equal to 50 wt. %, or greater than or equal to 60
wt. %, or greater than or equal to 70 wt. %, or greater than or
equal to 80 wt. %, or greater than or equal to 90 wt. % based on
the total weight of the lubricating oil.
[0018] "Minor amount" as it relates to components included within
the lubricating oils of the specification and the claims means less
than 50 wt. %, or less than or equal to 40 wt. %, or less than or
equal to 30 wt. %, or greater than or equal to 20 wt. %, or less
than or equal to 10 wt. %, or less than or equal to 5 wt. %, or
less than or equal to 2 wt. %, or less than or equal to 1 wt. %,
based on the total weight of the lubricating oil.
[0019] "Essentially free" as it relates to components included
within the lubricating oils of the specification and the claims
means that the particular component is at 0 weight % within the
lubricating oil, or alternatively is at impurity type levels within
the lubricating oil (less than 100 ppm, or less than 20 ppm, or
less than 10 ppm, or less than 1 ppm).
[0020] "Other lubricating oil additives" as used in the
specification and the claims means other lubricating oil additives
that are not specifically recited in the particular section of the
specification or the claims. For example, other lubricating oil
additives may include, but are not limited to, antioxidants,
detergents, dispersants, antiwear additives, corrosion inhibitors,
viscosity modifiers, metal passivators, pour point depressants,
seal compatibility agents, antifoam agents, extreme pressure
agents, friction modifiers and combinations thereof.
[0021] "Other mechanical component" or "mechanical component" as
used in the specification and the claims means an electric vehicle
component, a hybrid vehicle component, a power train, a driveline,
a transmission, a gear, a gear train, a gear set, a compressor, a
pump, a hydraulic system, a bearing, a bushing, a turbine, a
piston, a piston ring, a cylinder liner, a cylinder, a cam, a
tappet, a lifter, a gear, a valve, or a bearing including a
journal, a roller, a tapered, a needle, and a ball bearing.
[0022] "Hydrocarbon" refers to a compound consisting of carbon
atoms and hydrogen atoms.
[0023] "Alkane" refers to a hydrocarbon that is completely
saturated. An alkane can be linear, branched, cyclic, or
substituted cyclic.
[0024] "Olefin" refers to a non-aromatic hydrocarbon comprising one
or more carbon-carbon double bond in the molecular structure
thereof.
[0025] "Mono-olefin" refers to an olefin comprising a single
carbon-carbon double bond.
[0026] "Cn" group or compound refers to a group or a compound
comprising carbon atoms at total number thereof of n. Thus, "Cm-Cn"
group or compound refers to a group or compound comprising carbon
atoms at a total number thereof in the range from m to n. Thus, a
C1-C50 alkyl group refers to an alkyl group comprising carbon atoms
at a total number thereof in the range from 1 to 50.
[0027] "Carbon backbone" refers to the longest straight carbon
chain in the molecule of the compound or the group in question.
"Branch" refer to any substituted or unsubstituted hydrocarbyl
group connected to the carbon backbone. A carbon atom on the carbon
backbone connected to a branch is called a "branched carbon."
[0028] "Epsilon-carbon" in a branched alkane refers to a carbon
atom in its carbon backbone that is (i) connected to two hydrogen
atoms and two carbon atoms and (ii) connected to a branched carbon
via at least four (4) methylene (CH.sub.2) groups. Quantity of
epsilon carbon atoms in terms of mole percentage thereof in a
alkane material based on the total moles of carbon atoms can be
determined by using, e.g., .sup.13C NMR.
[0029] "Alpha-carbon" in a branched alkane refers to a carbon atom
in its carbon backbone that is with a methyl end with no branch on
the first 4 carbons. It is also measured in mole percentage using
.sup.13C NMR.
[0030] "T/P methyl" in a branched alkane refers to a methyl end and
a methyl in the 2 position. It is also measured in mole percentage
using .sup.13C NMR.
[0031] "P-methyl" in a branched alkane refers to a methyl branch
anywhere on the chain, except in the 2 position. It is also
measured in mole percentage using .sup.13C NMR.
[0032] "SAE" refers to SAE International, formerly known as Society
of Automotive Engineers, which is a professional organization that
sets standards for internal combustion engine lubricating oils.
[0033] "SAE J300" refers to the viscosity grade classification
system of engine lubricating oils established by SAE, which defines
the limits of the classifications in rheological terms only.
[0034] "Base stock" or "base oil" interchangeably refers to an oil
that can be used as a component of lubricating oils, heat transfer
oils, hydraulic oils, grease products, and the like.
[0035] "Lubricating oil" or "lubricant" interchangeably refers to a
substance that can be introduced between two or more surfaces to
reduce the level of friction between two adjacent surfaces moving
relative to each other. A lubricant base stock is a material,
typically a fluid at various levels of viscosity at the operating
temperature of the lubricant, used to formulate a lubricant by
admixing with other components. Non-limiting examples of base
stocks suitable in lubricants include API Group I, Group II, Group
III, Group IV, and Group V base stocks. PAOs, particularly
hydrogenated PAOs, have recently found wide use in lubricants as a
Group IV base stock, and are particularly preferred. If one base
stock is designated as a primary base stock in the lubricant,
additional base stocks may be called a co-base stock.
[0036] All kinematic viscosity values in this disclosure are as
determined pursuant to ASTM D445. Kinematic viscosity at
100.degree. C. is reported herein as KV100, and kinematic viscosity
at 40.degree. C. is reported herein as KV40. Unit of all KV100 and
KV40 values herein is cSt unless otherwise specified. When
describing the kinematic viscosity at 100.degree. C. is
"essentially" maintained, the kinematic viscosity at 100.degree. C.
is expected to vary less than 0.2 cSt as measured by ASTM D445.
[0037] All viscosity index ("VI") values in this disclosure are as
determined pursuant to ASTM D2270.
[0038] All Noack volatility ("NV") values in this disclosure are as
determined pursuant to ASTM D5800 unless specified otherwise. Unit
of all NV values is wt %, unless otherwise specified.
[0039] All pour point values in this disclosure are as determined
pursuant to ASTM D5950 or D97.
[0040] All CCS viscosity ("CCSV") values in this disclosure are as
determined pursuant to ASTM 5293. Unit of all CCSV values herein is
millipascal second (mPas), which is equivalent to centipoise),
unless specified otherwise. All CCSV values are measured at a
temperature of interest to the lubricating oil formulation or oil
composition in question. Thus, for the purpose of designing and
fabricating engine oil formulations, the temperature of interest is
the temperature at which the SAE J300 imposes a minimal CCSV.
[0041] All percentages in describing chemical compositions herein
are by weight unless specified otherwise. "Wt. %" means percent by
weight.
Lubricating Oil Compositions of This Disclosure
[0042] Air release, a measure of how fast air bubbles can escape
the bulk of a lubricant oil, is a very important performance
requirement for lubricants. Mainly determined by the viscosity and
chemistry of base oils, air release of a certain base oil
combinations cannot be improved by conventional additives. In
accordance with this disclosure, it has been found that the
addition of 7 wt % or less of an oil soluble polyalkylene glycol
can improve air release of a wide range of base stock combinations
ranging from Group I mineral oil to fully synthetic oils.
[0043] The lubricating oils of this disclosure have an oil soluble
polyalkylene glycol (OSP). It has been found that, with lubricating
oils having an oil soluble polyalkylene glycol, release of
entrained air in the lubricating oil is improved, as determined by
ASTM D-3427-15.
[0044] In an embodiment, the lubricating oil compositions of this
disclosure contain an oil soluble polyalkylene glycol along with
other typical lubricant additives. When all ingredients are present
in the appropriate concentrations, the lubricating oil formulations
of this disclosure provide improved air release as shown by testing
in the Examples.
[0045] The lubricant compositions of this disclosure provide
advantaged air release, when used in the lubrication of internal
combustion engines, power trains, drivelines, transmissions, gears,
gear trains, valve trains, gear sets, and the like, particularly
through the use of lubricating oil compositions having a specific
oil soluble polyalkylene glycol as described herein.
[0046] Also, the lubricant compositions of this disclosure provide
advantaged air release, in the lubrication of mechanical
components, which can include, for example, pistons, piston rings,
cylinder liners, cylinders, cams, tappets, lifters, bearings
(journal, roller, tapered, needle, ball, and the like), gears,
valves, and the like, particularly through the use of lubricating
oil compositions having a specific oil soluble polyalkylene glycol
as described herein.
[0047] Further, the lubricant compositions of this disclosure
provide advantaged air release, particularly through the use of
lubricating oil compositions having a specific oil soluble
polyalkylene glycol as a component in lubricant compositions, which
can include, for example, lubricating liquids, semi-solids, solids,
greases, dispersions, suspensions, material concentrates, additive
concentrates, and the like.
[0048] Also, the lubricant compositions of this disclosure provide
advantaged air release, in spark-ignition internal combustion
engines, compression-ignition internal combustion engines,
mixed-ignition (spark-assisted and compression) internal combustion
engines, and the like, particularly through the use of lubricating
oil compositions having a specific oil soluble polyalkylene glycol
as described herein.
[0049] Further, the lubricant compositions of this disclosure
provide advantaged air release, through the use of lubricating oil
compositions having a specific oil soluble polyalkylene glycol as
described herein, on lubricated surfaces that include, for example,
the following: metals, metal alloys, non-metals, non-metal alloys,
mixed carbon-metal composites and alloys, mixed carbon-nonmetal
composites and alloys, ferrous metals, ferrous composites and
alloys, non-ferrous metals, non-ferrous composites and alloys,
titanium, titanium composites and alloys, aluminum, aluminum
composites and alloys, magnesium, magnesium composites and alloys,
ion-implanted metals and alloys, plasma modified surfaces; surface
modified materials; coatings; mono-layer, multi-layer, and gradient
layered coatings; honed surfaces; polished surfaces; etched
surfaces; textured surfaces; micro and nano structures on textured
surfaces; super-finished surfaces; diamond-like carbon (DLC), DLC
with high-hydrogen content, DLC with moderate hydrogen content, DLC
with low-hydrogen content, DLC with near-zero hydrogen content, DLC
composites, DLC-metal compositions and composites, DLC-nonmetal
compositions and composites; ceramics, ceramic oxides, ceramic
nitrides, FeN, CrN, ceramic carbides, mixed ceramic compositions,
and the like; polymers, thermoplastic polymers, engineered
polymers, polymer blends, polymer alloys, polymer composites;
materials compositions and composites containing dry lubricants,
that include, for example, graphite, carbon, molybdenum, molybdenum
disulfide, polytetrafluoroethylene, polyperfluoropropylene,
polyperfluoroalkylethers, and the like.
[0050] During operation of a lubricating system containing the
lubricating oil of this disclosure, release of entrained air in the
lubricating oil is improved, as determined by ASTM D-3427-15, as
compared to release of entrained air achieved using a lubricating
oil containing other than the oil soluble polyalkylene glycol.
[0051] In an embodiment, during operation of a lubricating system
containing the lubricating oil of this disclosure, the time
required for entrained air content to fall to 0.2 volume percent,
as determined by ASTM D-3427-15, is reduced at least 5%, or at
least 10%, or at least 15%, or at least 20%, or at least 25%, or at
least 30%, or at least 35%, or at least 40%, or at least 45%, or at
least 50%, or at least 55%,or at least 60%, or at least 65%, or at
least 70%, or at least 75% or greater, as compared to the time
required for entrained air content to fall to 0.2 volume percent
using a lubricating oil containing other than the oil soluble
polyalkylene glycol.
Oil Soluble Polyalkylene Glycol (OSP) Additives
[0052] The lubricant formulations of this disclosure include an oil
soluble polyalkylene glycol (OSP). OSPs are miscible, preferably
soluble, in hydrocarbon base oils as is evident by their ability to
form a clear mixture as evaluated optically with an unaided
eye.
[0053] Polyalkylene glycols (PAGs) that comprise polymerized
alkylene oxides selected only from ethylene oxide and propylene
oxide are not considered OSPs. Desirably, the lubricant formulation
of the present disclosure is free of PAGs that comprise polymerized
alkylene oxides selected only from ethylene oxide and propylene
oxide, and can be free of PAGs that are not OSPs. PAGs generally
comprise an initiator component, a polyalkylene oxide component and
an end group at the end of each polyalkylene oxide chain opposite
from the initiator component.
[0054] The OSP of the present lubricant formulations is selected
from a monol, diol and triol initiated 1,2-butylene oxide
homopolymers, and monol initiated copolymers of 1,2-butylene oxide
and 1,2-propylene oxide (herein referred to simply as "propylene
oxide"). Preferably the 1,2-butylene oxide homopolymer is monol or
diol initiated, and most preferably monol initiated. Monols, diols
and triols are alcohols having from one to 18 carbon atoms,
preferably having six or more, more preferably eight or more and
still more preferably ten or more carbon atoms while at the same
time preferably having 16 or fewer, more preferably 14 or fewer and
most preferably 12 or fewer carbon atoms. Monols are alcohols with
a single hydroxyl group. Diols are alcohols with two hydroxyl
groups. Triols are alcohols with three hydroxyl groups. Examples of
desirable monol initiators include 1-dodecanol, butanol,
2-ethylhexanol, n-octanol, decanol, and oleyl alcohol. Examples of
suitable diols include ethylene glycol, 1,2-propylene glycol,
1,3-propylene glycol, and 1,4-butanediol. Examples of suitable
triols include glycerol and timethylolpropane.
[0055] The 1,2-butylene oxide homopolymer is initiated with a
monol, diol or triol and contains polymerized 1,2-butylene oxide as
its only polyalkylene oxide component. The copolymer of
1,2-butylene oxide and propylene oxide is initiated with a monol
and contains copolymerized 1,2-butylene oxide and propylene oxide
as its only polyalkylene oxide component. The copolymerized
1,2-butylene oxide and propylene oxide can be block or randomly
copolymerized, but is preferably randomly polymerized to form a
random copolymer. The OSP that is a copolymer of 1,2-butylene oxide
and propylene oxide desirably is made using 50 wt % or more
1,2-butylene oxide relative to total weight of 1,2-butylene oxide
and propylene oxide.
[0056] In an embodiment, the instant disclosure provides a
lubricant composition, in which the OSP comprises from 30 to 70
percent by weight units derived from propylene oxide and from 70 to
30 percent by weight units derived from butylene oxide.
[0057] All individual values and subranges from 30 to 70 percent by
weight units derived from propylene oxide are included herein and
disclosed herein; for example, the amount of units derived from
propylene oxide may range from a lower limit of 30, 40, 50, or 60
percent by weight to an upper limit of 35, 45, 55, 65, or 70
percent by weight. For example, the amount of units derived from
propylene oxide may range from 30 to 70 percent by weight, or in
the alternative, the amount of units derived from propylene oxide
may range from 40 to 60 percent by weight, or in the alternative,
the amount of units derived from propylene oxide may range from 40
to 70 percent by weight, or in the alternative, the amount of units
derived from propylene oxide may range from 45 to 55 percent by
weight, or in the alternative, the amount of units derived from
propylene oxide may be 50 percent by weight.
[0058] All individual values and subranges from 30 to 70 percent by
weight units derived from butylene oxide are included herein and
disclosed herein; for example, the amount of units derived from
butylene oxide may range from a lower limit of 30, 40, 50, or 60
percent by weight to an upper limit of 35, 45, 55, 65, or 70
percent by weight. For example, the amount of units derived from
butylene oxide may range from 30 to 70 percent by weight, or in the
alternative, the amount of units derived from butylene oxide may
range from 40 to 60 percent by weight, or in the alternative, the
amount of units derived from butylene oxide may range from 30 to 60
percent by weight, or in the alternative, the amount of units
derived from butylene oxide may range from 45 to 55 percent by
weight, or in the alternative, the amount of units derived from
butylene oxide may be 50 percent by weight.
[0059] The OSP can be capped or remain uncapped. If the OSP remains
uncapped, it terminates with a hydroxyl group (-OH) on the end
opposite from the alcohol initiator for each alkylene oxide polymer
chain extending from the alcohol initiator. Desirably, the OSP
remains uncapped. It can, however, be capped with groups such as
alkyl, aryl and alkylaryl groups.
[0060] One example of a desirable OSP is an uncapped
dodecanol-initiated random copolymer of 1,2-butylene oxide and
propylene oxide. Desirably the weight ratio of 1,2-butylene oxide
and propylene oxide is approximately 50:50. Alternatively, or
additionally, the copolymer has a molecular weight of 300 grams per
mole (g/mol) or more, preferably 400 g/mol or more, more preferably
450 g/mol or more and most preferably 500 g/mol or more while at
the same time has a molecular weight of 700 g/mol or less,
preferably 600 g/mole or less, more preferably 550 g/mol or less
and most preferably 500 g/mol or less.
[0061] In an embodiment, the OSP has a molecular weight from 400 to
1100 g/mole. All individual values and subranges are disclosed
herein and included herein; for example the molecular weight of the
OSP can range from a lower limit of 400, 500, 600, 700, 800, 900,
or 1000 g/mole to an upper limit of 450, 550, 650, 750, 850, 950,
1050 or 1100 g/mole. For example, the molecular weight of the OSP
may range from 400 to 1100 g/mole, or in the alternative, the
molecular weight of the OSP may range from 500 to 1000 g/mole, or
in the alternative, the molecular weight of the OSP may range from
400 to 800 g/mole, or in the alternative, the molecular weight of
the OSP may range from 600 to 1000 g/mole.
[0062] The OSP has a kinematic viscosity at 40.degree. C. from 15
cSt to 50 cSt. All individual values and subranges from 15 to 50
cSt are included herein and disclosed herein; for example, the
kinematic viscosity can be from a lower limit of 15, 20, 25, 30,
35, 40 or 45 cSt to an upper limit of 17.5, 22.5, 27.5, 32.5, 37.5,
42.5, 47.5 or 50 cSt. For example, the viscosity of the OSP can be
in a range of from 15 to 50 cSt, or in the alternative, the
viscosity of the OSP can be in a range of from 25 to 50 cSt, or in
the alternative, the viscosity of the OSP can be in a range of from
25 to 45 cSt, or in the alternative, the viscosity of the OSP can
be in a range of from 15 to 35 cSt, or in the alternative, the
viscosity of the OSP can be in a range of from 18 to 46 cSt.
[0063] Illustrative OSPs useful in this disclosure include, for
example, UCON.TM. OSP base fluids, commercially available from the
Dow Chemical Company, Midland, Michigan. UCON.TM. OSP base fluids
useful in this disclosure include, for example, OSP-18, OSP-32,
OSP-46, OSP-68, OSP-150, OSP-220, OSP-320, OSP-460, OSP-680, and
the like.
[0064] The OSP is present at a concentration of 7 wt % or less,
preferably 6.5 wt % or less and can be present at a concentration
of 5 wt % or less, 4.5 wt % or less, 4 wt % or less, even 3.5 wt %
or less. At the same time, the OSP is typically present at a
concentration of 5 wt % or less. Wt % is based on total lubricant
formulation weight.
[0065] All individual values and subranges from 0.1 to 7.5 percent
by weight OSP in the lubricant composition are included herein and
disclosed herein; for example, the OSP can range from a lower limit
of 0.1, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0 or 3.5 percent by weight to an
upper limit of 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0 or 7.25 percent by
weight. For example, the amount of OSP in the lubricant composition
may be from 0.5 to 5.5 percent by weight, or in the alternative,
the amount of OSP in the lubricant composition may be from 1.0 to
5.0 percent by weight, or in the alternative, the amount of OSP in
the lubricant composition may be from 1.5 to 4.5 percent by
weight.
[0066] The lubricating oil compositions of this disclosure are
obtained by incorporating an OSP component into a base oil,
however, depending on the lubricating oil used, known additives to
improve its characteristics, such as described herein can also be
incorporated as appropriate within a range such that the purpose of
this disclosure is not prejudiced. Normally, the total quantity of
these lubricating oil additives incorporated is preferably within
the range of about 0.05 to 25 wt. %, relative to the total weight
of the lubricant composition.
Lubricating Oil Base Stocks and Co-Base Stocks
[0067] A wide range of lubricating base oils is known in the art.
Lubricating base oils that are useful in the present disclosure are
natural oils, mineral 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.
[0068] Groups I, II, III, IV and V are broad base oil stock
categories developed and defined by the American Petroleum
Institute (API Publication 1509; www.API.org) to create guidelines
for lubricant base oils. Group I base stocks have a viscosity index
of between about 80 to 120 and contain greater than about 0.03%
sulfur and/or less than about 90% saturates. Group II base stocks
have a viscosity index of between about 80 to 120, and contain less
than or equal to about 0.03% sulfur and greater than or equal to
about 90% saturates. Group III stocks have a viscosity index
greater than about 120 and contain less than or equal to about
0.03% sulfur and greater than about 90% saturates. Group IV
includes polyalphaolefins (PAO). Group V base stock includes base
stocks not included in Groups I-IV. The table below summarizes
properties of each of these five groups.
TABLE-US-00001 Base Oil Properties Saturates Sulfur Viscosity Index
Group I <90 and/or >0.03% and .gtoreq.80 and <120 Group II
.gtoreq.90 and .ltoreq.0.03% and .gtoreq.80 and <120 Group III
.gtoreq.90 and .ltoreq.0.03% and .gtoreq.120 Group IV
polyalphaolefins (PAO) Group V All other base oil stocks not
included in Groups I, II, III or IV
[0069] 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.
[0070] Group II and/or Group III hydroprocessed or hydrocracked
base stocks are also well known base stock oils.
[0071] 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.
[0072] The number average molecular weights of the PAOs, which are
known materials and generally available on a major commercial scale
from suppliers such as ExxonMobil Chemical Company, Chevron
Phillips Chemical Company, BP, and others, typically vary from
about 250 to about 3,000, although PAO's may be made in viscosities
up to about 150 cSt (100.degree. C.). The PAOs are typically
comprised of relatively low molecular weight hydrogenated polymers
or oligomers of alphaolefins which include, but are not limited to,
C.sub.2 to about C.sub.32 alphaolefins with the C.sub.8 to about
C.sub.16 alphaolefins, such as 1-octene, 1-decene, 1-dodecene and
the like, being preferred. The preferred polyalphaolefins are
poly-1-octene, poly-1-decene and poly-1-dodecene and mixtures
thereof and mixed olefin-derived polyolefins. However, the dimers
of higher olefins in the range of C.sub.12 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 dimers, trimers and tetramers of the
starting olefins, with minor amounts of the lower and/or higher
oligomers, having a viscosity range of 1.5 cSt to 12 cSt. PAO
fluids of particular use may include 3 cSt, 3.4 cSt, and/or 3.6 cSt
and combinations thereof. Mixtures of PAO fluids having a viscosity
range of 1.5 cSt to approximately 150 cSt or more may be used if
desired. Unless indicated otherwise, all viscosities cited herein
are measured at 100.degree. C.
[0073] The PAO fluids may be conveniently made by the
polymerization of an alphaolefin in the presence of a
polymerization catalyst such as the Friedel-Crafts catalysts
including, for example, aluminum trichloride, boron trifluoride or
complexes of boron trifluoride with water, alcohols such as
ethanol, propanol or butanol, carboxylic acids or esters such as
ethyl acetate or ethyl propionate. For example, the methods
disclosed by U.S. Pat. Nos. 4,149,178 or 3,382,291 may be
conveniently used herein. Other descriptions of PAO synthesis are
found in the following U.S. Pat. Nos. 3,742,082; 3,769,363;
3,876,720; 4,239,930; 4,367,352; 4,413,156; 4,434,408; 4,910,355;
4,956,122; and 5,068,487. The dimers of the C.sub.14 to C.sub.18
olefins are described in U.S. Pat. No. 4,218,330.
[0074] Other useful lubricant oil base stocks include wax isomerate
base stocks and base oils, comprising hydroisomerized waxy stocks
(e.g. waxy stocks such as gas oils, slack waxes, fuels hydrocracker
bottoms, etc.), hydroisomerized Fischer-Tropsch waxes,
Gas-to-Liquids (GTL) base stocks and base oils, and other wax
isomerate hydroisomerized base stocks and base oils, or mixtures
thereof. Fischer-Tropsch waxes, the high boiling point residues of
Fischer-Tropsch synthesis, are highly paraffinic hydrocarbons with
very low sulfur content. The hydroprocessing used for the
production of such base stocks may use an amorphous
hydrocracking/hydroisomerization catalyst, such as one of the
specialized lube hydrocracking (LHDC) catalysts or a crystalline
hydrocracking/hydroisomerization catalyst, preferably a zeolitic
catalyst. For example, one useful catalyst is ZSM-48 as described
in U.S. Pat. No. 5,075,269, the disclosure of which is incorporated
herein by reference in its entirety. Processes for making
hydrocracked/hydroisomerized distillates and
hydrocracked/hydroisomerized waxes are described, for example, in
U.S. Pat. Nos. 2,817,693; 4,975,177; 4,921,594 and 4,897,178 as
well as in British Patent Nos. 1,429,494; 1,350,257; 1,440,230 and
1,390,359. Each of the aforementioned patents is incorporated
herein in their entirety. Particularly favorable processes are
described in European Patent Application Nos. 464546 and 464547,
also incorporated herein by reference. Processes using
Fischer-Tropsch wax feeds are described in U.S. Pat. Nos. 4,594,172
and 4,943,672, the disclosures of which are incorporated herein by
reference in their entirety.
[0075] Gas-to-Liquids (GTL) base oils, Fischer-Tropsch wax derived
base oils, and other wax-derived hydroisomerized (wax isomerate)
base oils may be advantageously used in the instant disclosure, and
may have useful kinematic viscosities at 100.degree. C. of about 2
cSt to about 50 cSt, preferably about 2 cSt to about 30 cSt, more
preferably about 3 cSt to about 25 cSt, as exemplified by GTL 4
with kinematic viscosity of about 4.0 cSt at 100.degree. C. and a
viscosity index of about 141. These Gas-to-Liquids (GTL) base oils,
Fischer-Tropsch wax derived base oils, and other wax-derived
hydroisomerized base oils may have useful pour points of about
-20.degree. C. or lower, and under some conditions may have
advantageous pour points of about -25.degree. C. or lower, with
useful pour points of about -30.degree. C. to about -40.degree. C.
or lower. Useful compositions of Gas-to-Liquids (GTL) base oils,
Fischer-Tropsch wax derived base oils, and wax-derived
hydroisomerized base oils are recited in U.S. Pat. Nos. 6,080,301;
6,090,989, and 6,165,949 for example, and are incorporated herein
in their entirety by reference.
[0076] The hydrocarbyl aromatics can be used as a base oil or base
oil component and can be any hydrocarbyl molecule that contains at
least about 5% of its weight derived from an aromatic moiety such
as a benzenoid moiety or naphthenoid moiety, or their derivatives.
These hydrocarbyl aromatics include alkyl benzenes, alkyl
naphthalenes, alkyl biphenyls, alkyl diphenyl oxides, alkyl
naphthols, alkyl diphenyl sulfides, alkylated bis-phenol A,
alkylated thiodiphenol, and the like. The aromatic can be
mono-alkylated, dialkylated, polyalkylated, and the like. The
aromatic can be mono- or poly-functionalized. The hydrocarbyl
groups can also be comprised of mixtures of alkyl groups, alkenyl
groups, alkynyl, cycloalkyl groups, cycloalkenyl groups and other
related hydrocarbyl groups. The hydrocarbyl groups can range from
about C.sub.6 up to about C.sub.60 with a range of about C.sub.8 to
about C.sub.20 often being preferred. A mixture of hydrocarbyl
groups is often preferred, and up to about three such substituents
may be present. The hydrocarbyl group can optionally contain
sulfur, oxygen, and/or nitrogen containing substituents. The
aromatic group can also be derived from natural (petroleum)
sources, provided at least about 5% of the molecule is comprised of
an above-type aromatic moiety. Viscosities at 100.degree. C. of
approximately 2 cSt to about 50 cSt are preferred, with viscosities
of approximately 3 cSt to about 20 cSt often being more preferred
for the hydrocarbyl aromatic component. In one embodiment, an alkyl
naphthalene where the alkyl group is primarily comprised of
1-hexadecene is used. Other alkylates of aromatics can be
advantageously used. Naphthalene or methyl naphthalene, for
example, can be alkylated with olefins such as octene, decene,
dodecene, tetradecene or higher, mixtures of similar olefins, and
the like. Alkylated naphthalene and analogues may also comprise
compositions with isomeric distribution of alkylating groups on the
alpha and beta carbon positions of the ring structure. Distribution
of groups on the alpha and beta positions of a naphthalene ring may
range from 100:1 to 1:100, more often 50:1 to 1:50 Useful
concentrations of hydrocarbyl aromatic in a lubricant oil
composition can be about 2% to about 50%, preferably about 4% to
about 20%, and more preferably about 4% to about 15%, depending on
the application.
[0077] Alkylated aromatics such as the hydrocarbyl aromatics of the
present disclosure may be produced by well-known Friedel-Crafts
alkylation of aromatic compounds. See Friedel-Crafts and Related
Reactions, Olah, G. A. (ed.), Inter-science Publishers, New York,
1963. For example, an aromatic compound, such as benzene or
naphthalene, is alkylated by an olefin, alkyl halide or alcohol in
the presence of a Friedel-Crafts catalyst. See Friedel-Crafts and
Related Reactions, Vol. 2, part 1, chapters 14, 17, and 18, See
Olah, G. A. (ed.), Inter-science Publishers, New York, 1964. Many
homogeneous or heterogeneous, solid catalysts are known to one
skilled in the art. The choice of catalyst depends on the
reactivity of the starting materials and product quality
requirements. For example, strong acids such as AlCl.sub.3,
BF.sub.3, or HF may be used. In some cases, milder catalysts such
as FeCl.sub.3 or SnCl.sub.4 are preferred. Newer alkylation
technology uses zeolites or solid super acids.
[0078] Esters comprise a useful base stock. Additive solvency and
seal compatibility characteristics may be secured by the use of
esters such as the esters of dibasic acids with monoalkanols and
the polyol esters of monocarboxylic acids. Esters of the former
type include, for example, the esters of dicarboxylic acids such as
phthalic acid, succinic acid, alkyl succinic acid, alkenyl succinic
acid, maleic acid, azelaic acid, suberic acid, sebacic acid,
fumaric acid, adipic acid, linoleic acid dimer, malonic acid, alkyl
malonic acid, alkenyl malonic acid, etc., with a variety of
alcohols such as butyl alcohol, hexyl alcohol, dodecyl alcohol,
2-ethylhexyl alcohol, etc. Specific examples of these types of
esters include dibutyl adipate, di(2-ethylhexyl) sebacate,
di-n-hexyl fumarate, dioctyl sebacate, diisooctyl azelate,
diisodecyl azelate, dioctyl phthalate, didecyl phthalate, dieicosyl
sebacate, etc.
[0079] Particularly useful synthetic esters are those which are
obtained by reacting one or more polyhydric alcohols, preferably
the hindered polyols (such as the neopentyl polyols, e.g.,
neopentyl glycol, trimethylol ethane,
2-methyl-2-propyl-1,3-propanediol, trimethylol propane,
pentaerythritol and dipentaerythritol) with alkanoic acids
containing at least about 4 carbon atoms, preferably C.sub.5 to
C.sub.30 acids such as saturated straight chain fatty acids
including caprylic acid, capric acid, lauric acid, myristic acid,
palmitic acid, stearic acid, arachic acid, and behenic acid, or the
corresponding branched chain fatty acids or unsaturated fatty acids
such as oleic acid, or mixtures of any of these materials.
[0080] Suitable synthetic ester components include the esters of
trimethylol propane, trimethylol butane, trimethylol ethane,
pentaerythritol and/or dipentaerythritol with one or more
monocarboxylic acids containing from about 5 to about 10 carbon
atoms. These esters are widely available commercially, for example,
the Mobil A-41 and A-51 esters of ExxonMobil Chemical Company.
[0081] 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 EsterexNP 343 ester of ExxonMobil
Chemical Company.
[0082] Engine oil formulations containing renewable esters are
included in this disclosure. For such formulations, the renewable
content of the ester is typically greater than about 70 weight
percent, preferably more than about 80 weight percent and most
preferably more than about 90 weight percent.
[0083] 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.
[0084] Non-conventional or unconventional base stocks/base oils
include one or more of a mixture of base stock(s) derived from one
or more Gas-to-Liquids (GTL) materials, as well as
isomerate/isodewaxate base stock(s) derived from natural wax or
waxy feeds, mineral and or non-mineral oil waxy feed stocks such as
slack waxes, natural waxes, and waxy stocks such as gas oils, waxy
fuels hydrocracker bottoms, waxy raffinate, hydrocrackate, thermal
crackates, or other mineral, mineral oil, or even non-petroleum oil
derived waxy materials such as waxy materials received from coal
liquefaction or shale oil, and mixtures of such base stocks.
[0085] GTL materials are materials that are derived via one or more
synthesis, combination, transformation, rearrangement, and/or
degradation/deconstructive processes from gaseous carbon-containing
compounds, hydrogen-containing compounds and/or elements as feed
stocks such as hydrogen, carbon dioxide, carbon monoxide, water,
methane, ethane, ethylene, acetylene, propane, propylene, propyne,
butane, butylenes, and butynes. GTL base stocks and/or base oils
are GTL materials of lubricating viscosity that are generally
derived from hydrocarbons; for example, waxy synthesized
hydrocarbons, that are themselves derived from simpler gaseous
carbon-containing compounds, hydrogen-containing compounds and/or
elements as feed stocks. GTL base stock(s) and/or base oil(s)
include oils boiling in the lube oil boiling range (1)
separated/fractionated from synthesized GTL materials such as, for
example, by distillation and subsequently subjected to a final wax
processing step which involves either or both of a catalytic
dewaxing process, or a solvent dewaxing process, to produce lube
oils of reduced/low pour point; (2) synthesized wax isomerates,
comprising, for example, hydrodewaxed or hydroisomerized cat and/or
solvent dewaxed synthesized wax or waxy hydrocarbons; (3)
hydrodewaxed or hydroisomerized cat and/or solvent dewaxed
Fischer-Tropsch (F-T) material (i.e., hydrocarbons, waxy
hydrocarbons, waxes and possible analogous oxygenates); preferably
hydrodewaxed or hydroisomerized/followed by cat and/or solvent
dewaxing dewaxed F-T waxy hydrocarbons, or hydrodewaxed or
hydroisomerized/followed by cat (or solvent) dewaxing dewaxed, F-T
waxes, or mixtures thereof.
[0086] GTL base stock(s) and/or base oil(s) derived from GTL
materials, especially, hydrodewaxed or hydroisomerized/followed by
cat and/or solvent dewaxed wax or waxy feed, preferably F-T
material derived base stock(s) and/or base oil(s), are
characterized typically as having kinematic viscosities at
100.degree. C. of from about 2 mm.sup.2/s to about 50 mm.sup.2/s
(ASTM D445).
[0087] They are further characterized typically as having pour
points of -5.degree. C. to about -40.degree. C. or lower (ASTM
D97). They are also characterized typically as having viscosity
indices of about 80 to about 140 or greater (ASTM D2270).
[0088] In addition, the GTL base stock(s) and/or base oil(s) are
typically highly paraffinic (>90% saturates), and may contain
mixtures of monocycloparaffins and multicycloparaffins in
combination with non-cyclic isoparaffins. The ratio of the
naphthenic (i.e., cycloparaffin) content in such combinations
varies with the catalyst and temperature used. Further, GTL base
stock(s) and/or base oil(s) typically have very low sulfur and
nitrogen content, generally containing less than about 10 ppm, and
more typically less than about 5 ppm of each of these elements. The
sulfur and nitrogen content of GTL base stock(s) and/or base oil(s)
obtained from F-T material, especially F-T wax, is essentially nil.
In addition, the absence of phosphorus and aromatics make this
materially especially suitable for the formulation of low SAP
products.
[0089] 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.
[0090] 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).
[0091] 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.
[0092] 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 about 6 to about 99 weight
percent or from about 6 to about 95 weight percent, preferably from
about 50 to about 99 weight percent or from about 70 to about 95
weight percent, and more preferably from about 85 to about 95
weight percent, based on the total weight of the composition. The
base oil 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 about 2.5 cSt
to about 18 cSt (or mm.sup.2 /s) at 100.degree. C. and preferably
of about 2.5 cSt to about 12.5 cSt (or mm.sup.2/s) at 100.degree.
C., often more preferably from about 2.5 cSt to about 10 cSt.
Mixtures of synthetic and natural base oils may be used if desired.
Bi-modal, tri-modal, and additional combinations of mixtures of
Group I, II, III, IV, and/or V base stocks may be used if
desired.
[0093] The co-base stock component is present in an amount
sufficient for providing solubility, compatibility and dispersancy
of polar additives in the lubricating oil. The co-base stock
component is present in the lubricating oils of this disclosure in
an amount from about 1 to about 99 weight percent, preferably from
about 5 to about 95 weight percent, and more preferably from about
10 to about 90 weight percent.
Other Lubricating Oil Additives
[0094] The formulated lubricating oil useful in the present
disclosure may additionally contain one or more of the other
commonly used lubricating oil performance additives including but
not limited to antiwear additives, dispersants, detergents,
viscosity modifiers, corrosion inhibitors, rust inhibitors, metal
deactivators, extreme pressure additives, anti-seizure agents, wax
modifiers, viscosity modifiers, fluid-loss additives, seal
compatibility agents, lubricity agents, anti-staining agents,
chromophoric agents, defoamants, demulsifiers, densifiers, wetting
agents, gelling agents, tackiness agents, colorants, and others.
For a review of many commonly used additives, see Klamann in
Lubricants and Related Products, Verlag Chemie, Deerfield Beach,
FL; ISBN 0-89573-177-0. Reference is also made to "Lubricant
Additives" by M. W. Ranney, published by Noyes Data Corporation of
Parkridge, NJ (1973); see also U.S. Pat. No. 7,704,930, the
disclosure of which is incorporated herein in its entirety. These
additives are commonly delivered with varying amounts of diluent
oil, that may range from 5 weight percent to 50 weight percent.
[0095] The additives useful in this disclosure do not have to be
soluble in the lubricating oils. Insoluble additives in oil can be
dispersed in the lubricating oils of this disclosure.
[0096] 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 Additives
[0097] A metal alkylthiophosphate and more particularly a metal
dialkyl dithio phosphate in which the metal constituent is zinc, or
zinc dialkyl dithio phosphate (ZDDP) can be a useful component of
the lubricating oils of this disclosure. ZDDP can be derived from
primary alcohols, secondary alcohols or mixtures thereof. ZDDP
compounds generally are of the formula
Zn[SP(S)(OR.sup.1)(OR.sup.2)].sub.2
where R.sup.1 and R.sup.2 are C.sub.1-C.sub.18 alkyl groups,
preferably C.sub.2-C.sub.12 alkyl groups. These alkyl groups may be
straight chain or branched. Alcohols used in the ZDDP can be
propanol, 2-propanol, butanol, secondary butanol, pentanols,
hexanols such as 4-methyl-2-pentanol, n-hexanol, n-octanol, 2-ethyl
hexanol, alkylated phenols, and the like. Mixtures of secondary
alcohols or of primary and secondary alcohol can be preferred.
Alkyl aryl groups may also be used.
[0098] 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".
[0099] The ZDDP is typically used in amounts of from about 0.3
weight percent to about 1.5 weight percent, preferably from about
0.4 weight percent to about 1.2 weight percent, more preferably
from about 0.5 weight percent to about 1.0 weight percent, and even
more preferably from about 0.6 weight percent to about 0.8 weight
percent, based on the total weight of the lubricating oil, although
more or less can often be used advantageously. Preferably, the ZDDP
is a secondary ZDDP and present in an amount of from about 0.6 to
1.0 weight percent of the total weight of the lubricating oil.
Dispersants
[0100] 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 dispersants are considered ashless. In
contrast, metal-containing detergents discussed above form ash upon
combustion.
[0101] 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.
[0102] Illustrative dispersants useful in this disclosure include,
for example, (poly)alkenylsuccinic derivatives, polyisobutylene
succinimide (PIBSA) having a basic nitrogen content of about 1% or
greater, succinimides, hydrocarbyl-substituted succinic acids,
hydrocarbyl-substituted succinic anhydride derivatives, or mixtures
thereof, all having a basic nitrogen content of about 1% or
greater.
[0103] A useful class of dispersants are the (poly)alkenylsuccinic
derivatives, typically produced by the reaction of a long chain
hydrocarbyl substituted succinic compound, usually a hydrocarbyl
substituted succinic anhydride, with a polyhydroxy or polyamino
compound. The long chain hydrocarbyl group constituting the
oleophilic portion of the molecule which confers solubility in the
oil, is normally a polyisobutylene group. Many examples of this
type of dispersant are well known commercially and in the
literature. Exemplary U.S. patents describing such dispersants are
U.S. Pat. Nos. 3,172,892; 3,2145,707; 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.
[0104] 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.
[0105] Succinimides are formed by the condensation reaction between
hydrocarbyl substituted succinic anhydrides and amines Molar ratios
can vary depending on the polyamine. For example, the molar ratio
of hydrocarbyl substituted succinic anhydride to TEPA can vary from
about 1:1 to about 5:1. Representative examples are shown in U.S.
Pat. Nos. 3,087,936; 3,172,892; 3,219,666; 3,272,746; 3,322,670;
and 3,652,616, 3,948,800; and Canada Patent No. 1,094,044.
[0106] 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.
[0107] 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.
[0108] The molecular weight of the hydrocarbyl substituted succinic
anhydrides used in the preceding paragraphs will typically range
between 800 and 2,500 or more. The above products can be
post-reacted with various reagents such as sulfur, oxygen,
formaldehyde, carboxylic acids such as oleic acid. The above
products can also be post reacted with boron compounds such as
boric acid, borate esters or highly borated dispersants, to form
borated dispersants generally having from about 0.1 to about 5
moles of boron per mole of dispersant reaction product.
[0109] Suitable dispersants include succinimides, including those
derivatives from mono-succinimides, bis-succinimides, and/or
mixtures of mono- and bis-succinimides, wherein the hydrocarbyl
succinimide is derived from a hydrocarbylene group such as
polyisobutylene having a Mn of from about 500 to about 5000, or
from about 1000 to about 3000, or about 1000 to about 2000, or a
mixture of such hydrocarbylene groups, often with high terminal
vinylic groups. Other preferred dispersants include succinic
acid-esters and amides, alkylphenol-polyamine-coupled Mannich
adducts, their capped derivatives, and other related
components.
[0110] Illustrative dispersants useful in this disclosure include
those derived from polyalkenyl-substituted mono- or dicarboxylic
acid, anhydride or ester, which dispersant has a polyalkenyl moiety
with a number average molecular weight of at least 900 and from
greater than 1.3 to 1.7, preferably from greater than 1.3 to 1.6,
most preferably from greater than 1.3 to 1.5, functional groups
(mono- or dicarboxylic acid producing moieties) per polyalkenyl
moiety (a medium functionality dispersant). Functionality (F) can
be determined according to the following formula:
F=(SAP.times.M.sub.n)/((112,200.times.A.I.)-(SAP-98))
wherein SAP is the saponification number (i.e., the number of
milligrams of KOH consumed in the complete neutralization of the
acid groups in one gram of the succinic-containing reaction
product, as determined according to ASTM D94); M.sub.r, is the
number average molecular weight of the starting olefin polymer; and
A.I. is the percent active ingredient of the succinic-containing
reaction product (the remainder being unreacted olefin polymer,
succinic anhydride and diluent).
[0111] The polyalkenyl moiety of the dispersant may have a number
average molecular weight of at least 900, suitably at least 1500,
preferably between 1800 and 3000, such as between 2000 and 2800,
more preferably from about 2100 to 2500, and most preferably from
about 2200 to about 2400. The molecular weight of a dispersant is
generally expressed in terms of the molecular weight of the
polyalkenyl moiety. This is because the precise molecular weight
range of the dispersant depends on numerous parameters including
the type of polymer used to derive the dispersant, the number of
functional groups, and the type of nucleophilic group employed.
[0112] Polymer molecular weight, specifically M.sub.n, can be
determined by various known techniques. One convenient method is
gel permeation chromatography (GPC), which additionally provides
molecular weight distribution information (see W. W. Yau, J. J.
Kirkland and D. D. Bly, "Modern Size Exclusion Liquid
Chromatography", John Wiley and Sons, New York, 1979). Another
useful method for determining molecular weight, particularly for
lower molecular weight polymers, is vapor pressure osmometry (e.g.,
ASTM D3592).
[0113] The polyalkenyl moiety in a dispersant preferably has a
narrow molecular weight distribution (MWD), also referred to as
polydispersity, as determined by the ratio of weight average
molecular weight (M.sub.w) to number average molecular weight
(M.sub.n). Polymers having a M.sub.w/M.sub.n of less than 2.2,
preferably less than 2.0, are most desirable. Suitable polymers
have a polydispersity of from about 1.5 to 2.1, preferably from
about 1.6 to about 1.8.
[0114] Suitable polyalkenes employed in the formation of the
dispersants include homopolymers, interpolymers or lower molecular
weight hydrocarbons. One family of such polymers comprise polymers
of ethylene and/or at least one C.sub.3 to C.sub.2 alpha-olefin
having the formula H.sub.2C=CHR.sup.1 wherein IV is a straight or
branched chain alkyl radical comprising 1 to 26 carbon atoms and
wherein the polymer contains carbon-to-carbon unsaturation, and a
high degree of terminal ethenylidene unsaturation. Preferably, such
polymers comprise interpolymers of ethylene and at least one
alpha-olefin of the above formula, wherein R.sup.1 is alkyl of from
1 to 18 carbon atoms, and more preferably is alkyl of from 1 to 8
carbon atoms, and more preferably still of from 1 to 2 carbon
atoms.
[0115] Another useful class of polymers is polymers prepared by
cationic polymerization of monomers such as isobutene and styrene.
Common polymers from this class include polyisobutenes obtained by
polymerization of a C.sub.4 refinery stream having a butene content
of 35 to 75% by weight, and an isobutene content of 30 to 60% by
weight. A preferred source of monomer for making poly-n-butenes is
petroleum feedstreams such as Raffinate II. These feedstocks are
disclosed in the art such as in U.S. Pat. No. 4,952,739. A
preferred embodiment utilizes polyisobutylene prepared from a pure
isobutylene stream or a Raffinate I stream to prepare reactive
isobutylene polymers with terminal vinylidene olefins.
Polyisobutene polymers that may be employed are generally based on
a polymer chain of from 1500 to 3000.
[0116] The dispersant(s) are preferably non-polymeric (e.g., mono-
or bis-succinimides). Such dispersants can be prepared by
conventional processes such as disclosed in U.S. Patent Application
Publication No. 2008/0020950, the disclosure of which is
incorporated herein by reference.
[0117] Other 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.
[0118] 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.
[0119] 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 HNR2 group-containing reactants.
[0120] 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.
[0121] Polymethacrylate or polyacrylate derivatives are another
class of dispersants. These dispersants are typically prepared by
reacting a nitrogen containing monomer and a methacrylic or acrylic
acid esters containing 5 -25 carbon atoms in the ester group.
Representative examples are shown in U.S. Pat. Nos. 2, 100, 993,
and 6,323,164. Polymethacrylate and polyacrylate dispersants are
normally used as multifunctional viscosity modifiers. The lower
molecular weight versions can be used as lubricant dispersants or
fuel detergents.
[0122] The dispersant(s) can be borated by conventional means, as
generally disclosed in U.S. Pat. Nos. 3,087,936, 3,254,025 and
5,430,105.
[0123] Such dispersants may be used in an amount of about 0.001 to
20 weight percent or 0.01 to 10 weight percent, preferably about
0.5 to 8 weight percent, or more preferably 0.5 to 4 weight
percent. Or such dispersants may be used in an amount of about 2 to
12 weight percent, preferably about 4 to 10 weight percent, or more
preferably 6 to 9 weight percent. On an active ingredient basis,
such additives may be used in an amount of about 0.06 to 14 weight
percent, preferably about 0.3 to 6 weight percent.
[0124] As used herein, the dispersant concentrations are given on
an "as delivered" basis. Typically, the active dispersant is
delivered with a process oil. The "as delivered" dispersant
typically contains from about 20 weight percent to about 80 weight
percent, or from about 40 weight percent to about 60 weight
percent, of active dispersant in the "as delivered" dispersant
product.
Detergents
[0125] Illustrative detergents (e.g., non-borated) useful in this
disclosure include, for example, alkali metal detergents, alkaline
earth metal detergents, or mixtures of one or more alkali metal
detergents and one or more alkaline earth metal detergents. A
typical detergent is an anionic material that contains a long chain
hydrophobic portion of the molecule and a smaller anionic or
oleophobic hydrophilic portion of the molecule. The anionic portion
of the detergent is typically derived from an organic acid such as
a sulfur-containing acid, carboxylic acid (e.g., salicylic acid),
phosphorus-containing acid, phenol, or mixtures thereof. The
counterion is typically an alkaline earth or alkali metal. The
detergent can be overbased. Non-borated or borated detergents can
be used.
[0126] The detergent can be a metal salt of an organic or inorganic
acid, a metal salt of a phenol, or mixtures thereof. The metal can
be an alkali metal, an alkaline earth metal, and mixtures thereof.
The organic or inorganic acid is selected from an aliphatic organic
or inorganic acid, a cycloaliphatic organic or inorganic acid, an
aromatic organic or inorganic acid, and mixtures thereof.
[0127] The metal can be an alkali metal, an alkaline earth metal,
and mixtures thereof. Particularly, the metal can be calcium (Ca),
magnesium (Mg), and mixtures thereof.
[0128] The organic acid or inorganic acid can be a
sulfur-containing acid, a carboxylic acid, a phosphorus-containing
acid, and mixtures thereof.
[0129] In an embodiment, the metal salt of an organic or inorganic
acid or the metal salt of a phenol can be calcium phenate,
magnesium phenate, an overbased detergent, and mixtures
thereof.
[0130] Salts that contain a substantially stochiometric amount of
the metal are described as neutral salts and have a total base
number (TBN, as measured by ASTM D2896) of from 0 to 80. Many
compositions are overbased, containing large amounts of a metal
base that is achieved by reacting an excess of a metal compound (a
metal hydroxide or oxide, for example) with an acidic gas (such as
carbon dioxide). Useful detergents can be neutral, mildly
overbased, or highly overbased. These detergents can be used in
mixtures of neutral, overbased, highly overbased calcium phenates
and/or magnesium phenates. The TBN ranges can vary from low, medium
to high TBN products, including as low as 0 to as high as 600. The
TBN delivered by the detergent is between 1 and 20. The TBN
delivered by the detergent can be between 1 and 12. Mixtures of
low, medium, high TBN can be used, along with mixtures of calcium
and magnesium metal based detergents, and including phenates and
carboxylates. A detergent mixture with a metal ratio of 1, in
conjunction of a detergent with a metal ratio of 2, and as high as
a detergent with a metal ratio of 5, can be used. Non-borated or
borated detergents can be used.
[0131] Alkaline earth phenates are another useful class of
detergent. These detergents can be made by reacting alkaline earth
metal hydroxide or oxide (CaO, Ca(OH).sub.2, BaO, Ba(OH).sub.2,
MgO, Mg(OH).sub.2, for example) with an alkyl phenol or sulfurized
alkylphenol. Useful alkyl groups include straight chain or branched
C.sub.1-C.sub.30 alkyl groups, particularly, 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.
[0132] Alkaline earth metal phosphates are also used as detergents
and are known in the art.
[0133] 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.
[0134] Illustrative detergents include calcium phenates, magnesium
phenates, and other related components (including borated
detergents), and mixtures thereof. Illustrative mixtures of
detergents include calcium phenate and magnesium phenate. Overbased
detergents are also used. One example of a borated calcium
sulfonate detergent is OLOA 10400X.
[0135] The detergent concentration in the lubricating oils of this
disclosure can range from about 0.5 to about 6.0 weight percent,
preferably about 0.6 to 5.0 weight percent, and more preferably
from about 0.8 weight percent to about 4.0 weight percent, based on
the total weight of the lubricating oil. For lower soap
concentrations, the detergent concentration in the lubricating oils
of this disclosure can range from about 0.5 to about 6.0 weight
percent, preferably about 1.0 to 3.0 weight percent, and more
preferably from about 1.5 weight percent to about 2.5 weight
percent, based on the total weight of the lubricating oil. For
higher soap concentrations, the detergent concentration in the
lubricating oils of this disclosure can range from about 0.5 to
about 6.0 weight percent, preferably about 1.0 to 5.5 weight
percent, and more preferably from about 3.0 weight percent to about
4.0 weight percent, based on the total weight of the lubricating
oil.
[0136] As used herein, the detergent concentrations are given on an
"as delivered" basis. Typically, the active detergent is delivered
with a process oil. The "as delivered" detergent typically contains
from about 20 weight percent to about 100 weight percent, or from
about 40 weight percent to about 60 weight percent, of active
detergent in the "as delivered" detergent product.
Viscosity Modifiers
[0137] Viscosity modifiers (also known as viscosity index improvers
(VI improvers), and viscosity improvers) can be included in the
lubricant compositions of this disclosure.
[0138] Viscosity modifiers provide lubricants with high and low
temperature operability. These additives impart shear stability at
elevated temperatures and acceptable viscosity at low
temperatures.
[0139] Suitable viscosity modifiers include high molecular weight
hydrocarbons, polyesters and viscosity modifier dispersants that
function as both a viscosity modifier and a dispersant. Typical
molecular weights of these polymers are between about 10,000 to
1,500,000, more typically about 20,000 to 1,200,000, and even more
typically between about 50,000 and 1,000,000.
[0140] Examples of suitable viscosity modifiers are linear or
star-shaped polymers and copolymers of methacrylate, butadiene,
olefins, or alkylated styrenes. Polyisobutylene is a commonly used
viscosity modifier. Another suitable viscosity modifier is
polymethacrylate (copolymers of various chain length alkyl
methacrylates, for example), some formulations of which also serve
as pour point depressants. Other suitable viscosity modifiers
include copolymers of ethylene and propylene, hydrogenated block
copolymers of styrene and isoprene, and polyacrylates (copolymers
of various chain length acrylates, for example). Specific examples
include styrene-isoprene or styrene-butadiene based polymers of
50,000 to 200,000 molecular weight.
[0141] Olefin copolymers are commercially available from Chevron
Oronite Company LLC under the trade designation "PARATONE.RTM."
(such as "PARATONE.RTM. 8921" and "PARATONE.RTM. 8941"); from Afton
Chemical Corporation under the trade designation "HiTEC.RTM." (such
as "HiTEC.RTM. 5850B"; and from The Lubrizol Corporation under the
trade designation "Lubrizol.RTM. 7067C". Hydrogenated polyisoprene
star polymers are commercially available from Infineum
International Limited, e.g., under the trade designation "SV200"
and "SV600". Hydrogenated diene-styrene block copolymers are
commercially available from Infineum International Limited, e.g.,
under the trade designation "SV 50".
[0142] The polymethacrylate or polyacrylate polymers can be linear
polymers which are available from Evnoik Industries under the trade
designation "Viscoplex.RTM." (e.g., Viscoplex 6-954) or star
polymers which are available from Lubrizol Corporation under the
trade designation Asteric.TM. (e.g., Lubrizol 87708 and Lubrizol
87725).
[0143] Illustrative vinyl aromatic-containing polymers useful in
this disclosure may be derived predominantly from vinyl aromatic
hydrocarbon monomer. Illustrative vinyl aromatic-containing
copolymers useful in this disclosure may be represented by the
following general formula:
A-B
wherein A is a polymeric block derived predominantly from vinyl
aromatic hydrocarbon monomer, and B is a polymeric block derived
predominantly from conjugated diene monomer.
[0144] In an embodiment of this disclosure, the viscosity modifiers
may be used in an amount of less than about 10 weight percent,
preferably less than about 7 weight percent, more preferably less
than about 4 weight percent, and in certain instances, may be used
at less than 2 weight percent, preferably less than about 1 weight
percent, and more preferably less than about 0.5 weight percent,
based on the total weight of the formulated oil or lubricating
engine oil. Viscosity modifiers are typically added as
concentrates, in large amounts of diluent oil.
[0145] As used herein, the viscosity modifier concentrations are
given on an "as delivered" basis. Typically, the active polymer is
delivered with a diluent oil. The "as delivered" viscosity modifier
typically contains from 20 weight percent to 75 weight percent of
an active polymer for polymethacrylate or polyacrylate polymers, or
from 8 weight percent to 20 weight percent of an active polymer for
olefin copolymers, hydrogenated polyisoprene star polymers, or
hydrogenated diene-styrene block copolymers, in the "as delivered"
polymer concentrate.
Antioxidants
[0146] 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.
[0147] Useful antioxidants include hindered phenols. These phenolic
antioxidants may be ashless (metal-free) phenolic compounds or
neutral or basic metal salts of certain phenolic compounds. Typical
phenolic antioxidant compounds are the hindered phenolics which are
the ones which contain a sterically hindered hydroxyl group, and
these include those derivatives of dihydroxy aryl compounds in
which the hydroxyl groups are in the o- or p-position to each
other. Typical phenolic antioxidants include the hindered phenols
substituted with C.sub.6+ alkyl groups and the alkylene coupled
derivatives of these hindered phenols. Examples of phenolic
materials of this type 2-t-butyl-4-heptyl phenol; 2-t-butyl-4-octyl
phenol; 2-t-butyl-4-dodecyl phenol; 2,6-di-t-butyl-4-heptyl phenol;
2,6-di-t-butyl-4-dodecyl phenol; 2-methyl-6-t-butyl-4-heptyl
phenol; and 2-methyl-6-t-butyl-4-dodecyl phenol. Other useful
hindered mono-phenolic antioxidants may include for example
hindered 2,6-di-alkyl-phenolic proprionic ester derivatives.
Bis-phenolic antioxidants may also be advantageously used in
combination with the instant disclosure. Examples of ortho-coupled
phenols include: 2,2'-bis(4-heptyl-6-t-butyl-phenol);
2,2'-bis(4-octyl-6-t-butyl-phenol); and
2,2'-bis(4-dodecyl-6-t-butyl-phenol). Para-coupled bisphenols
include for example 4,4'-bis(2,6-di-t-butyl phenol) and
4,4'-methylene-bis(2,6-di-t-butyl phenol).
[0148] Effective amounts of one or more catalytic antioxidants may
also be used. The catalytic antioxidants comprise an effective
amount of a) one or more oil soluble polymetal organic compounds;
and, effective amounts of b) one or more substituted
N,N'-diaryl-o-phenylenediamine compounds or c) one or more hindered
phenol compounds; or a combination of both b) and c). Catalytic
antioxidants are more fully described in U.S. Pat. No. 8, 048,833,
herein incorporated by reference in its entirety.
[0149] Non-phenolic oxidation inhibitors which may be used include
aromatic amine antioxidants and these may be used either as such or
in combination with phenolics. Typical examples of non-phenolic
antioxidants include: alkylated and non-alkylated aromatic amines
such as aromatic monoamines of the formula R.sup.8R.sup.9R.sup.10N
where R.sup.8 is an aliphatic, aromatic or substituted aromatic
group, R.sup.9 is an aromatic or a substituted aromatic group, and
R.sup.10 is H, alkyl, aryl or R.sup.11S(O).sub.XR.sup.12 where
R.sup.11 is an alkylene, alkenylene, or aralkylene group, R.sup.12
is a higher alkyl group, or an alkenyl, aryl, or alkaryl group, and
x is 0, 1 or 2. The aliphatic group R.sup.8 may contain from 1 to
about 20 carbon atoms, and preferably contains from about 6 to 12
carbon atoms. The aliphatic group is a saturated aliphatic group.
Preferably, both R.sup.8 and R.sup.9 are aromatic or substituted
aromatic 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.
[0150] Typical aromatic amines antioxidants have alkyl substituent
groups of at least about 6 carbon atoms. Examples of aliphatic
groups include hexyl, heptyl, octyl, nonyl, and decyl. Generally,
the aliphatic groups will not contain more than about 14 carbon
atoms. The general types of amine antioxidants useful in the
present compositions include diphenylamines, phenyl naphthylamines,
phenothiazines, imidodibenzyls and diphenyl phenylene diamines
Mixtures of two or more aromatic amines are also useful. Polymeric
amine antioxidants can also be used. Particular examples of
aromatic amine antioxidants useful in the present disclosure
include: p,p'-dioctyldiphenylamine; t-octylphenyl-
alpha-naphthylamine; phenyl-alphanaphthylamine; and p-octylphenyl-
alpha-naphthylamine
[0151] Sulfurized alkyl phenols and alkali or alkaline earth metal
salts thereof also are useful antioxidants.
[0152] Preferred antioxidants include hindered phenols, arylamines
These antioxidants may be used individually by type or in
combination with one another. Such additives may be used in an
amount of about 0.01 to 5 weight percent, preferably about 0.01 to
1.5 weight percent, more preferably zero to less than 1.5 weight
percent, more preferably zero to less than 1 weight percent.
Pour Point Depressants (PPDs)
[0153] Conventional pour point depressants (also known as lube oil
flow improvers) may be added to the compositions of the present
disclosure if desired. These pour point depressant may be added to
lubricating compositions of the present disclosure to lower the
minimum temperature at which the fluid will flow or can be poured.
Examples of suitable pour point depressants include
polymethacrylates, polyacrylates, polyarylamides, condensation
products of haloparaffin waxes and aromatic compounds, vinyl
carboxylate polymers, and terpolymers of dialkylfumarates, vinyl
esters of fatty acids and allyl vinyl ethers. U.S. Pat. Nos.
1,815,022; 2,015,748; 2,191,498; 2,387,501; 2,655, 479; 2,666,746;
2,721,877; 2,721,878; and 3,250,715 describe useful pour point
depressants and/or the preparation thereof. Such additives may be
used in an amount of about 0.01 to 5 weight percent, preferably
about 0.01 to 1.5 weight percent.
Seal Compatibility Agents
[0154] Seal compatibility agents help to swell elastomeric seals by
causing a chemical reaction in the fluid or physical change in the
elastomer. Suitable seal compatibility agents for lubricating oils
include organic phosphates, aromatic esters, aromatic hydrocarbons,
esters (butylbenzyl phthalate, for example), and polybutenyl
succinic anhydride. Such additives may be used in an amount of
about 0.01 to 3 weight percent, preferably about 0.01 to 2 weight
percent.
Antifoam Agents
[0155] Anti-foam agents may advantageously be added to lubricant
compositions. These agents retard the formation of stable foams.
Silicones and organic polymers are typical anti-foam agents. For
example, polysiloxanes, such as silicon oil or polydimethyl
siloxane, provide antifoam properties. Anti-foam agents are
commercially available and may be used in conventional minor
amounts along with other additives such as demulsifiers; usually
the amount of these additives combined is less than 1 weight
percent and often less than 0.1 weight percent.
Inhibitors and Antirust Additives
[0156] 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.
[0157] One type of antirust additive is a polar compound that wets
the metal surface preferentially, protecting it with a film of oil.
Another type of antirust additive absorbs water by incorporating it
in a water-in-oil emulsion so that only the oil touches the metal
surface. Yet another type of antirust additive chemically adheres
to the metal to produce a non-reactive surface. Examples of
suitable additives include zinc dithiophosphates, metal phenolates,
basic metal sulfonates, fatty acids and amines Such additives may
be used in an amount of about 0.01 to 5 weight percent, preferably
about 0.01 to 1.5 weight percent.
Friction Modifiers
[0158] 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 lube
compositions of this disclosure.
[0159] Illustrative friction modifiers may include, for example,
organometallic compounds or materials, or mixtures thereof.
Illustrative organometallic friction modifiers useful in the
lubricating engine oil formulations of this disclosure include, for
example, molybdenum amine, molybdenum diamine, an
organotungstenate, a molybdenum dithiocarbamate, molybdenum
dithiophosphates, molybdenum amine complexes, molybdenum
carboxylates, and the like, and mixtures thereof. Similar tungsten
based compounds may be preferable.
[0160] Other illustrative friction modifiers useful in the
lubricating engine oil formulations of this disclosure include, for
example, alkoxylated fatty acid esters, alkanolamides, polyol fatty
acid esters, borated glycerol fatty acid esters, fatty alcohol
ethers, and mixtures thereof.
[0161] Illustrative alkoxylated fatty acid esters include, for
example, polyoxyethylene stearate, fatty acid polyglycol ester, and
the like. These can include polyoxypropylene stearate,
polyoxybutylene stearate, polyoxyethylene isosterate,
polyoxypropylene isostearate, polyoxyethylene palmitate, and the
like.
[0162] Illustrative alkanolamides include, for example, lauric acid
diethylalkanolamide, palmic acid diethylalkanolamide, and the like.
These can include oleic acid diethyalkanolamide, stearic acid
diethylalkanolamide, oleic acid diethylalkanolamide,
polyethoxylated hydrocarbylamides, polypropoxylated
hydrocarbylamides, and the like.
[0163] Illustrative polyol fatty acid esters include, for example,
glycerol mono-oleate, saturated mono-, di-, and tri-glyceride
esters, glycerol mono-stearate, and the like. These can include
polyol esters, hydroxyl-containing polyol esters, and the like.
[0164] Illustrative borated glycerol fatty acid esters include, for
example, borated glycerol mono-oleate, borated saturated mono-,
di-, and tri-glyceride esters, borated glycerol mono-sterate, and
the like. In addition to glycerol polyols, these can include
trimethylolpropane, pentaerythritol, sorbitan, and the like. These
esters can be polyol monocarboxylate esters, polyol dicarboxylate
esters, and on occasion polyoltricarboxylate esters. Preferred can
be the glycerol mono-oleates, glycerol dioleates, glycerol
trioleates, glycerol monostearates, glycerol distearates, and
glycerol tristearates and the corresponding glycerol
monopalmitates, glycerol dipalmitates, and glycerol tripalmitates,
and the respective isostearates, linoleates, and the like. On
occasion the glycerol esters can be preferred as well as mixtures
containing any of these. Ethoxylated, propoxylated, butoxylated
fatty acid esters of polyols, especially using glycerol as
underlying polyol can be preferred.
[0165] Illustrative fatty alcohol ethers include, for example,
stearyl ether, myristyl ether, and the like. Alcohols, including
those that have carbon numbers from C.sub.3 to C.sub.50, can be
ethoxylated, propoxylated, or butoxylated to form the corresponding
fatty alkyl ethers. The underlying alcohol portion can preferably
be stearyl, myristyl, C.sub.11-C.sub.13 hydrocarbon, oleyl,
isosteryl, and the like.
[0166] The lubricating oils of this disclosure exhibit desired
properties, e.g., wear control, in the presence or absence of a
friction modifier.
[0167] Useful concentrations of friction modifiers may range from
0.01 weight percent to 5 weight percent, or about 0.1 weight
percent to about 2.5 weight percent, or about 0.1 weight percent to
about 1.5 weight percent, or about 0.1 weight percent to about 1
weight percent. Concentrations of molybdenum-containing materials
are often described in terms of Mo metal concentration.
Advantageous concentrations of Mo may range from 25 ppm to 700 ppm
or more, and often with a preferred range of 50-200 ppm. Friction
modifiers of all types may be used 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.
[0168] When lubricating oil compositions contain one or more of the
additives discussed above, the additive(s) are blended into the
composition in an amount sufficient for it to perform its intended
function. Typical amounts of such additives useful in the present
disclosure are shown in Table 1 below.
[0169] 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 Lubricating Oil
Components Approximate Approximate Wt. % Wt. % Compound (Useful)
(Preferred) Polyalkylene Glycol 0.1-7 0.1-5 Dispersant 0.1-20 0.1-8
Detergent 0.1-20 0.1-8 Friction Modifier 0.01-5 0.01-1.5
Antioxidant 0.1-8 0.1-3 Pour Point Depressant 0.0-5 0.01-1.5 (PPD)
Anti-foam Agent 0.001-3 0.001-0.2 Viscosity Modifier 0.1-2 0.1-1
(solid polymer basis) Antiwear 0.2-3 0.5-1 Inhibitor and Antirust
0.01-5 0.01-1.5
[0170] 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.
[0171] The lubricating oils of this disclosure have utility in
automotive, commercial, and industrial applications.
[0172] The following non-limiting examples are provided to
illustrate the disclosure.
EXAMPLES
[0173] All of the ingredients used herein are commercially
available. The additive package used herein is commercially
available from Afton Chemical. Lubricating oil formulations were
prepared as described herein.
[0174] The additive package used in the formulations included
conventional additives in conventional amounts. Additives used in
the formulations were one or more of an antioxidant, dispersant,
ashless antiwear agent, extreme pressure agent, and metal
(molybdenum). Optional additives were one or more of a corrosion
inhibitor, metal passivator, pour point depressant, metal
deactivator, seal compatibility additive, antifoam agent, and
friction modifier.
[0175] Lubricating oils were prepared by blending at least one
lubricating oil base stock with one or more lubricating oil
additives selected from an antioxidant, dispersant, ashless
antiwear agent, extreme pressure agent, and metal (molybdenum). An
OSP was blended into the lubricating oil. The OSP was UCON.TM. OSP
32 which is a random copolymer of butylene oxide and propylene
oxide and having a molecular weight around 760 g/mole.
[0176] Five base stock combinations were formulated with and
without 7% UCON.TM. OSP 32. Each combination was carefully tuned to
have similar viscosity at 40.degree. C. Four viscosity grades,
namely VG 18, 32, 68 and 320, were selected. Formulation 1: VG 68,
Core.TM. 600/Core.TM. 150 (Group I base stocks) with and without
UCON.TM. OSP 32. Formulation 2: VG 32, Core.TM. 600/Core.TM. 150
(Group I base stocks) with and without UCON.TM. OSP 32. Formulation
3: VG 32, QHVI 8/QHVI 4 (Group III base stocks) with and without
UCON.TM. OSP 32. Formulation 4: VG 320, PAO 100/PAO 6 (Group IV
base stocks) with and without UCON.TM. OSP 32. Formulation 5: VG
18, PAO 4/MCP 2481/Ditridecyl phthalate (Group IV base stocks) with
and without UCON.TM. OSP 32. The improvement in air release was
observed in all five base stock combinations. Greater improvement
was observed in more viscous formulations. The formulation
concentrations are provided in FIG. 1. As shown in FIG. 1, air
release is improved significantly by blending the base stock with
the OSP.
[0177] Release of entrained air in the lubricating oil was
determined by ASTM D-3427-15.
[0178] In another example, a comparative VG 580 was prepared using
bright stock. The inventive formulation included a VG 580 using
bright stock with 3% OSP18. As can be seen in Table 2 below, there
is a 3 minute reduction on air release with the use of the OSP in
the formulation.
TABLE-US-00003 TABLE 2 Inventive Comparative (3% OSP18) Americas
Core 83 America core 70 2500 (Group I 2500 Base stock) Naphthenic
17 Naphthenic 27 Bright Stock Bright Stock KV40 586 UCON OSP18 3
KV100 33.85 576.4 D3427-4, air 25 32.34 release 75.degree. C.,
D3427-4, air 22 min release 75.degree. C., min
PCT and EP Clauses:
[0179] 1. A lubricating oil having a composition comprising: at
least one lubricating oil base stock as a major component, and one
or more lubricating oil additives, as a minor component; wherein
the one or more lubricating oil additives comprise at least one
polyalkylene glycol, and is other than a sulfurized olefin; wherein
the at least one polyalkylene glycol is soluble in the at least one
lubricating oil base stock; wherein the weight ratio of the at
least one polyalkylene glycol to the at least one lubricating oil
base stock is from 1:99 to 7:93; wherein, during operation of a
lubricating system containing the lubricating oil, release of
entrained air in the lubricating oil is improved, as determined by
ASTM D-3427-15, as compared to release of entrained air achieved
using a lubricating oil containing other than the at least one
polyalkylene glycol. lubricating oil having a composition
comprising: at least one lubricating oil base stock as a major
component, and one or more lubricating oil additives, as a minor
component; wherein the one or more lubricating oil additives
comprise at least one polyalkylene glycol, and is other than a
sulfurized olefin; wherein the at least one polyalkylene glycol is
soluble in the at least one lubricating oil base stock; wherein the
weight ratio of the at least one polyalkylene glycol to the at
least one lubricating oil base stock is from 1:99 to 7:93; wherein,
during operation of a lubricating system containing the lubricating
oil, release of entrained air in the lubricating oil is improved,
as determined by ASTM D-3427-15, as compared to release of
entrained air achieved using a lubricating oil containing other
than the at least one polyalkylene glycol.
[0180] 2. The lubricating oil of clause 1 wherein, during operation
of a lubricating system containing the lubricating oil, the time
required for entrained air content to fall to 0.2 volume percent,
as determined by ASTM D-3427-15, is reduced at least 5%, as
compared to the time required for entrained air content to fall to
0.2 volume percent, using a lubricating oil containing other than
the at least one polyalkylene glycol.
[0181] 3. The lubricating oil of clause 1 wherein, during operation
of a lubricating system containing the lubricating oil, the time
required for entrained air content to fall to 0.2 volume percent,
as determined by ASTM D-3427-15, is reduced at least 10%, as
compared to the time required for entrained air content to fall to
0.2 volume percent, using a lubricating oil containing other than
the at least one polyalkylene glycol.
[0182] 4. The lubricating oil of clauses 1-3 wherein the weight
ratio of the at least one polyalkylene glycol to the at least one
lubricating oil base stock is from 1:99 to 6.5:93.5.
[0183] 5. The lubricating oil of clauses 1-3 wherein the weight
ratio of the at least one polyalkylene glycol to the at least one
lubricating oil base stock is from 1:99 to 4.5:95.5.
[0184] 6. The lubricating oil of clauses 1-3 wherein the at least
one polyalkylene glycol comprises from 25 to 75 weight percent
units derived from butylene oxide and from 25 to 75 weight percent
units derived from propylene oxide, initiated by one or more
initiators selected from monols, diols and polyols.
[0185] 7. The lubricating oil of clauses 1-3 wherein the at least
one polyalkylene glycol comprises from 45 to 55 weight percent
units derived from butylene oxide and 45 to 55 weight percent units
derived from propylene oxide, initiated by one or more monol
initiators.
[0186] 8. The lubricating oil of clauses 1-3 wherein the at least
one polyalkylene glycol is selected from the group consisting of
copolymers comprising units derived from propylene oxide and
butylene oxide, polybutylene oxide homopolymer, and combinations
thereof.
[0187] 9. The lubricating oil of clauses 1-3 wherein the at least
one polyalkylene glycol has a kinematic viscosity (KV.sub.40) from
15 to 100 cSt at 40.degree. C. as determined by ASTM D-445-19, and
a molecular weight from 400 to 1100 grams/mole.
[0188] 10. The lubricating oil of clauses 1-3 wherein the
lubricating oil base stock comprises a Group I, Group II, Group
III, Group IV or Group V base oil.
[0189] 11. The lubricating oil of clauses 1-3 wherein the
lubricating oil base stock is present in an amount of from 75
weight percent to 95 weight percent, and the at least one
polyalkylene glycol is present in an amount from 1 to 7 weight
percent, based on the total weight of the lubricating oil.
[0190] 12. The lubricating oil of clauses 1-3 wherein the one or
more lubricating oil additives further comprise one or more of an
antiwear additive, viscosity modifier, antioxidant, detergent,
dispersant, pour point depressant, corrosion inhibitor, metal
deactivator, seal compatibility additive, antifoam agent,
inhibitor, friction modifier, and anti-rust additive.
[0191] 13. A method for improving air release in a lubricating oil,
said method comprising: formulating a composition comprising at
least one lubricating oil base stock as a major component, and one
or more lubricating oil additives, as a minor component; wherein
the one or more lubricating oil additives comprise at least one
polyalkylene glycol, and is other than a sulfurized olefin; wherein
the at least one polyalkylene glycol is soluble in the at least one
lubricating oil base stock; wherein the weight ratio of the at
least one polyalkylene glycol to the at least one lubricating oil
base stock is from 1:99 to 7:93; wherein, during operation of a
lubricating system containing the lubricating oil, release of
entrained air in the lubricating oil is improved, as determined by
ASTM D-3427-15, as compared to release of entrained air achieved
using a lubricating oil containing other than the at least one
polyalkylene glycol.
[0192] 14. The method of clause 13 wherein, during operation of a
lubricating system containing the lubricating oil, the time
required for entrained air content to fall to 0.2 volume percent,
as determined by ASTM D-3427-15, is reduced at least 5%, as
compared to the time required for entrained air content to fall to
0.2 volume percent, using a lubricating oil containing other than
the at least one polyalkylene glycol.
[0193] 15. The method of clause 13 wherein, during operation of a
lubricating system containing the lubricating oil, the time
required for entrained air content to fall to 0.2 volume percent,
as determined by ASTM D-3427-15, is reduced at least 10%, as
compared to the time required for entrained air content to fall to
0.2 volume percent, using a lubricating oil containing other than
the at least one polyalkylene glycol.
[0194] 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.
[0195] When numerical lower limits and numerical upper limits are
listed herein, ranges from any lower limit to any upper limit are
contemplated. While the illustrative embodiments of the disclosure
have been described with particularity, it will be understood that
various other modifications will be apparent to and can be readily
made by those skilled in the art without departing from the spirit
and scope of the disclosure. Accordingly, it is not intended that
the scope of the claims appended hereto be limited to the examples
and descriptions set forth herein but rather that the claims be
construed as encompassing all the features of patentable novelty
which reside in the present disclosure, including all features
which would be treated as equivalents thereof by those skilled in
the art to which the disclosure pertains.
[0196] The present disclosure has been described above with
reference to numerous embodiments and specific examples. Many
variations will suggest themselves to those skilled in this art in
light of the above detailed description. All such obvious
variations are within the full intended scope of the appended
claims.
* * * * *
References