U.S. patent application number 16/108352 was filed with the patent office on 2019-02-28 for ashless engine lubricants for high temperature applications.
The applicant listed for this patent is ExxonMobil Research and Engineering Company. Invention is credited to Matthew W. BOLAND, Eugine CHOI, Zhisheng GAO, Luca SALVI.
Application Number | 20190062667 16/108352 |
Document ID | / |
Family ID | 63490706 |
Filed Date | 2019-02-28 |
United States Patent
Application |
20190062667 |
Kind Code |
A1 |
GAO; Zhisheng ; et
al. |
February 28, 2019 |
ASHLESS ENGINE LUBRICANTS FOR HIGH TEMPERATURE APPLICATIONS
Abstract
An ashless lubricating oil having a lubricating oil base stock
as a major component, and a mixture of (i) at least one ashless
antiwear additive, (ii) at least one ashless detergent, and (iii)
at least one aminic antioxidant, as minor components. The
lubricating oil base stock is a branched polyol ester. The
lubricating oil base stock is present in an amount from about 30 to
about 99.8 mass percent, based on the total mass of the ashless
lubricating oil. A method for improving oxidative stability and
high temperature stability of a lubricating oil in an engine or
other mechanical component lubricated with the lubricating oil by
using the ashless lubricating oil. The ashless lubricating oil is
useful as a passenger vehicle engine oil (PVEO).
Inventors: |
GAO; Zhisheng; (Rose Valley,
PA) ; SALVI; Luca; (Haddonfield, NJ) ; CHOI;
Eugine; (Marlton, NJ) ; BOLAND; Matthew W.;
(Philadelphia, PA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ExxonMobil Research and Engineering Company |
Annandale |
NJ |
US |
|
|
Family ID: |
63490706 |
Appl. No.: |
16/108352 |
Filed: |
August 22, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62550117 |
Aug 25, 2017 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C10M 133/12 20130101;
C10M 2223/065 20130101; C10M 2215/065 20130101; C10M 2207/2835
20130101; C10N 2040/255 20200501; C10M 2207/026 20130101; C10N
2030/45 20200501; C10N 2030/10 20130101; C10M 137/14 20130101; C10M
2209/104 20130101; C10M 2209/105 20130101; C10M 2215/064 20130101;
C10N 2040/252 20200501; C10M 161/00 20130101; C10M 169/044
20130101; C10M 2207/2805 20130101; C10M 2290/04 20130101; C10M
2209/106 20130101; C10N 2030/04 20130101; C10M 135/06 20130101;
C10M 2219/024 20130101; C10M 2223/063 20130101; C10N 2020/071
20200501; C10N 2030/08 20130101; C10M 169/04 20130101; C10M
2201/085 20130101; C10M 2223/047 20130101; C10M 105/38 20130101;
C10M 145/36 20130101; C10M 2209/105 20130101; C10M 2209/108
20130101; C10M 2209/104 20130101; C10M 2209/108 20130101; C10M
2209/106 20130101; C10M 2209/108 20130101 |
International
Class: |
C10M 169/04 20060101
C10M169/04; C10M 137/14 20060101 C10M137/14; C10M 135/06 20060101
C10M135/06; C10M 145/36 20060101 C10M145/36; C10M 133/12 20060101
C10M133/12; C10M 161/00 20060101 C10M161/00 |
Claims
1. A method for improving oxidative stability of a lubricating oil
in an engine or other mechanical component lubricated with the
lubricating oil by using as the lubricating oil an ashless
formulated oil, said ashless formulated oil having a composition
comprising a lubricating oil base stock as a major component; and a
mixture of (i) at least one ashless antiwear additive, (ii) at
least one ashless detergent, and (iii) at least one aminic
antioxidant, as minor components; wherein the lubricating oil base
stock comprises at least one branched polyol ester, which is
obtained by reacting one or more polyhydric alcohols with one or
more branched mono-carboxylic acids containing at least 4 carbon
atoms, and wherein the lubricating oil base stock is present in an
amount from 30 to 99.8 mass percent, based on the total mass of the
lubricating oil.
2. The method of claim 1 wherein oxidative stability is improved,
as compared to oxidative stability achieved using a lubricating oil
other than the ashless formulated oil.
3. The method of claim 1 wherein the one or more polyhydric
alcohols are selected from the group consisting of trimethylol
propane, pentaerythritol, neopentyl glycol, trimethylol ethane,
2-methyl-2-propyl-1,3-propanediol, and dipentaerythritol.
4. The method of claim 1 wherein the one or more branched
mono-carboxylic acids containing at least 4 carbon atoms are
selected from the group consisting of 3,5,5-trimethyl hexanoic acid
(TMH), 2,2-dimethyl propionic acid (neopentanoic acid),
neoheptanoic acid, neooctanoic acid, neononanoic acid, iso-hexanoic
acid, neodecanoic acid, 2-ethyl hexanoic acid (2EH), isoheptanoic
acid, isooctanoic acid, isononanoic acid, and isodecanoic acid.
5. The method of claim 1 wherein the at least one branched polyol
ester is selected from the group consisting of trimethylol propane
ester of 3,5,5-trimethyl hexanoic acid (TMH), trimethylol propane
ester of 2,2-dimethyl propionic acid (neopentanoic acid),
trimethylol propane ester of neoheptanoic acid, trimethylol propane
ester of neooctanoic acid, trimethylol propane ester of neononanoic
acid, trimethylol propane ester of iso-hexanoic acid, trimethylol
propane ester of neodecanoic acid, trimethylol propane ester of
2-ethyl hexanoic acid (2EH), trimethylol propane ester of
isoheptanoic acid, trimethylol propane ester of isooctanoic acid,
trimethylol propane ester of isononanoic acid, and trimethylol
propane ester of isodecanoic acid.
6. The method of claim 1 wherein the at least one branched polyol
ester is selected from the group consisting of pentaerythritol
ester of 3,5,5-trimethyl hexanoic acid (TMH), pentaerythritol ester
of 2,2-dimethyl propionic acid (neopentanoic acid), pentaerythritol
ester of neoheptanoic acid, pentaerythritol ester of neooctanoic
acid, pentaerythritol ester of neononanoic acid, pentaerythritol
ester of iso-hexanoic acid, pentaerythritol ester of neodecanoic
acid, pentaerythritol ester of 2-ethyl hexanoic acid (2EH),
pentaerythritol ester of isoheptanoic acid, pentaerythritol ester
of isooctanoic acid, pentaerythritol ester of isononanoic acid, and
pentaerythritol ester of isodecanoic acid.
7. The method of claim 1 wherein the at least one ashless antiwear
additive is selected from the group consisting of an amine
phosphate, a thiophosphate, a dithiophosphate, an amine salt of
sulfurized phosphate, an alkylated triphenyl phosphorothionate, a
sulfurized triglyceride, and mixtures thereof.
8. The method of claim 1 wherein the at least one ashless detergent
is selected from the group consisting of a polyoxyethylene alkyl
ether, a polyoxypropylene alkyl ether, and a polyoxybutylene alkyl
ether.
9. The method of claim 1 wherein the at least one aminic
antioxidant is selected from the group consisting of
p,p'-dioctyldiphenylamine, octylated phenyl-alpha-naphthylamine,
octylated/butylated diphenylamine, and a polymeric aminic
antioxidant.
10. The method of claim 9 wherein the polymeric aminic antioxidant
is the polymerization reaction product of one or more substituted
or hydrocarbyl-substituted diphenyl amines, one or more
unsubstituted or hydrocarbyl-substituted phenyl naphthyl amines, or
a combination thereof.
11. The method of claim 1 wherein the at least one ashless antiwear
additive is present in an amount from 0.01 to 1.2 mass percent,
based on the total mass of the lubricating oil.
12. The method of claim 1 wherein the at least one ashless
detergent is present in an amount from 0.01 to 6 mass percent,
based on the total mass of the lubricating oil.
13. The method of claim 1 wherein the at least one aminic
antioxidant is present in an amount from 0.01 to 15 mass percent,
based on the total mass of the lubricating oil.
14. The method of claim 1 wherein the ashless formulated oil
further comprises one or more of a viscosity modifier, dispersant,
pour point depressant, corrosion inhibitor, metal deactivator, seal
compatibility additive, anti-foam agent, inhibitor, and anti-rust
additive.
15. The method of claim 1 wherein the engine or other mechanical
component comprises a high energy density gasoline engine equipped
with turbo chargers, or gasoline particular filters (GPFs).
16. The method of claim 1 wherein the lubricating oil is a
passenger vehicle engine oil (PVEO).
17. An ashless lubricating oil having a composition comprising a
lubricating oil base stock as a major component; and a mixture of
(i) at least one ashless antiwear additive, (ii) at least one
ashless detergent, and (iii) at least one aminic antioxidant, as
minor components; wherein the lubricating oil base stock comprises
at least one branched polyol ester, which is obtained by reacting
one or more polyhydric alcohols with one or more branched
mono-carboxylic acids containing at least 4 carbon atoms; and
wherein the lubricating oil base stock is present in an amount from
30 to 99.8 mass percent, based on the total mass of the ashless
lubricating oil.
18. The ashless lubricating oil of claim 17 wherein, in an engine
or other mechanical component lubricated with the ashless
lubricating oil, oxidative stability is improved achieved using a
lubricating oil other than the ashless lubricating oil.
19. The ashless lubricating oil of claim 17 wherein the one or more
polyhydric alcohols are selected from the group consisting of
trimethylol propane, pentaerythritol, neopentyl glycol, trimethylol
ethane, 2-methyl-2-propyl-1,3-propanediol, and
dipentaerythritol.
20. The ashless lubricating oil of claim 17 wherein the one or more
branched mono-carboxylic acids containing at least 4 carbon atoms
are selected from the group consisting of 3,5,5-trimethyl hexanoic
acid (TMH), 2,2-dimethyl propionic acid (neopentanoic acid),
neoheptanoic acid, neooctanoic acid, neononanoic acid, iso-hexanoic
acid, neodecanoic acid, 2-ethyl hexanoic acid (2EH), isoheptanoic
acid, isooctanoic acid, isononanoic acid, and isodecanoic acid.
21. The ashless lubricating oil of claim 17 wherein the at least
one branched polyol ester is selected from the group consisting of
trimethylol propane ester of 3,5,5-trimethyl hexanoic acid (TMH),
trimethylol propane ester of 2,2-dimethyl propionic acid
(neopentanoic acid), trimethylol propane ester of neoheptanoic
acid, trimethylol propane ester of neooctanoic acid, trimethylol
propane ester of neononanoic acid, trimethylol propane ester of
iso-hexanoic acid, trimethylol propane ester of neodecanoic acid,
trimethylol propane ester of 2-ethyl hexanoic acid (2EH),
trimethylol propane ester of isoheptanoic acid, trimethylol propane
ester of isooctanoic acid, trimethylol propane ester of isononanoic
acid, and trimethylol propane ester of isodecanoic acid.
22. The ashless lubricating oil of claim 17 wherein the at least
one branched polyol ester is selected from the group consisting of
pentaerythritol ester of 3,5,5-trimethyl hexanoic acid (TMH),
pentaerythritol ester of 2,2-dimethyl propionic acid (neopentanoic
acid), pentaerythritol ester of neoheptanoic acid, pentaerythritol
ester of neooctanoic acid, pentaerythritol ester of neononanoic
acid, pentaerythritol ester of iso-hexanoic acid, pentaerythritol
ester of neodecanoic acid, pentaerythritol ester of 2-ethyl
hexanoic acid (2EH), pentaerythritol ester of isoheptanoic acid,
pentaerythritol ester of isooctanoic acid, pentaerythritol ester of
isononanoic acid, and pentaerythritol ester of isodecanoic
acid.
23. The ashless lubricating oil of claim 17 wherein the at least
one ashless antiwear additive is selected from the group consisting
of an amine phosphate, a thiophosphate, a dithiophosphate, an amine
salt of sulfurized phosphate, an alkylated triphenyl
phosphorothionate, a sulfurized triglyceride, and mixtures
thereof.
24. The ashless lubricating oil of claim 17 wherein the at least
one ashless detergent is selected from the group consisting of a
polyoxyethylene alkyl ether, a polyoxypropylene alkyl ether, and a
polyoxybutylene alkyl ether.
25. The ashless lubricating oil of claim 17 wherein the at least
one aminic antioxidant is selected from the group consisting of
p,p'-dioctyldiphenylamine, octylated phenyl-alpha-naphthylamine,
octylated/butylated diphenylamine, and a polymeric aminic
antioxidant.
26. The ashless lubricating oil of claim 25 wherein the polymeric
aminic antioxidant is the polymerization reaction product of one or
more substituted or hydrocarbyl-substituted diphenyl amines, one or
more unsubstituted or hydrocarbyl-substituted phenyl naphthyl
amines, or a combination thereof.
27. The ashless lubricating oil of claim 17 wherein the at least
one ashless antiwear additive is present in an amount from 0.01 to
1.2 mass percent, based on the total mass of the lubricating
oil.
28. The ashless lubricating oil of claim 17 wherein the at least
one ashless detergent is present in an amount from 0.01 to 6 mass
percent, based on the total mass of the lubricating oil.
29. The ashless lubricating oil of claim 17 wherein the at least
one aminic antioxidant is present in an amount from 0.01 to 15 mass
percent, based on the total mass of the lubricating oil.
30. The ashless lubricating oil of claim 17 further comprising one
or more of a viscosity modifier, dispersant, pour point depressant,
corrosion inhibitor, metal deactivator, seal compatibility
additive, anti-foam agent, inhibitor, and anti-rust additive.
31. The ashless lubricating oil of claim 17 wherein the engine or
other mechanical component comprises a high energy density gasoline
engine equipped with turbo chargers, or gasoline particular filters
(GPFs).
32. The ashless lubricating oil of claim 17 which is a passenger
vehicle engine oil (PVEO).
33. A method for improving high temperature stability of a
lubricating oil in an engine or other mechanical component
lubricated with the lubricating oil by using as the lubricating oil
an ashless formulated oil, said ashless formulated oil having a
composition comprising a lubricating oil base stock as a major
component; and a mixture of (i) at least one ashless antiwear
additive, (ii) at least one ashless detergent, and (iii) at least
one aminic antioxidant, as minor components; wherein the
lubricating oil base stock comprises at least one branched polyol
ester, which is obtained by reacting one or more polyhydric
alcohols with one or more branched mono-carboxylic acids containing
at least 4 carbon atoms, and at least one alkylated naphthalene;
and wherein the lubricating oil base stock is present in an amount
from 30 to 99.8 mass percent, based on the total mass of the
lubricating oil.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application No. 62/550,117, filed on Aug. 25, 2017, the entire
contents of which are incorporated herein by reference.
FIELD
[0002] This disclosure relates to ashless engine lubricating oils
for high temperature applications. In particular, this disclosure
relates to ashless lubricating oils, methods for improving
oxidative stability in an engine or other mechanical component
lubricated with an ashless lubricating oil, and methods for
improving high temperature stability of a lubricating oil in an
engine or other mechanical component lubricated with an ashless
lubricating oil. The ashless lubricating oils of this disclosure
are useful as passenger vehicle engine oil (PVEO) products,
especially for engines equipped with turbo chargers, or diesel or
gasoline particular filters (DPFs or GPFs).
BACKGROUND
[0003] In today's high energy density engines, lubricants
experience much higher temperatures than in the past and in some
parts of the engines (e.g., the turbo chargers), the temperature
can reach 200.degree. C. or higher. In addition, there are
advantages in running an engine hotter while maintaining a low air
intake temperature. One such advantage is to reduce the need for
cooling.
[0004] General Motors has disclosed the use of an automated air
shutter system that reduces the wind drag at high vehicle speed
when the temperature is not too high, resulting in a fuel
efficiency of nearly half a mile per gallon in combined city and
highway driving for the 2011 Chevrolet Cruze Eco (see GM Corporate
Newsroom, Unique Air Shutter Helps Morph Chevrolet Cruze into 40
MPG Leader, 2010-08-10).
[0005] Further, GPFs are being used in direct injection gasoline
engines to meet the particular emission requirements. Studies have
shown that engine oil ash level could have impacts on GPF
performance and service life (N. C. Custer "Ash Impacts on Gasoline
Particular Filter Performance and Service Life", Master Thesis,
MIT, June 2015). What is needed is an ashless engine oil that is
beneficial to GPFs.
SUMMARY
[0006] This disclosure relates in part to new ashless lubricating
oil formulations which are useful in high temperature applications
such as high energy density engines equipped with turbo chargers.
This disclosure also relates in part to new ashless lubricating oil
formulations having high temperature stability sufficient to reduce
engine cooling needs (smaller radiator or less wind drag), and
sufficient to reduce water contamination (for engines equipped with
water injection technology).
[0007] This disclosure also relates in part to a method for
improving oxidative stability of a lubricating oil, in an engine or
other mechanical component lubricated with the lubricating oil by
using as the lubricating oil an ashless formulated oil. The ashless
formulated oil has a composition comprising a lubricating oil base
stock as a major component, and a mixture of (i) at least one
ashless antiwear additive, (ii) at least one ashless detergent, and
(iii) at least one aminic antioxidant, as minor components. The
lubricating oil base stock is at least one branched polyol ester,
which is obtained by reacting one or more polyhydric alcohols with
one or more branched mono-carboxylic acids containing at least
about 4 carbon atoms, or at least one alkylated naphthalene. The
lubricating oil base stock is present in an amount from about 30 to
about 99.8 mass percent, based on the total mass of the lubricating
oil.
[0008] This disclosure further relates in part to a method for
improving oxidative stability of a lubricating oil in an engine or
other mechanical component lubricated with the lubricating oil by
using as the lubricating oil an ashless formulated oil. The ashless
formulated oil has a composition comprising a lubricating oil base
stock as a major component, and at least one ashless antiwear
additive, as a minor component. The lubricating oil base stock is
at least one branched polyol ester, which is obtained by reacting
one or more polyhydric alcohols with one or more branched
mono-carboxylic acids containing at least about 4 carbon atoms. The
lubricating oil base stock is present in an amount from about 30 to
about 99.8 mass percent, based on the total mass of the lubricating
oil.
[0009] This disclosure yet further relates in part to an ashless
lubricating oil having a composition comprising a lubricating oil
base stock as a major component, and a mixture of (i) at least one
ashless antiwear additive, (ii) at least one ashless detergent, and
(iii) at least one aminic antioxidant, as minor components. The
lubricating oil base stock is at least one branched polyol ester,
which is obtained by reacting one or more polyhydric alcohols with
one or more branched mono-carboxylic acids containing at least
about 4 carbon atoms. The lubricating oil base stock is present in
an amount from about 30 to about 99.8 mass percent, based on the
total mass of the ashless lubricating oil.
[0010] This disclosure also relates in part to an ashless
lubricating oil having a composition comprising a lubricating oil
base stock. The lubricating oil base stock is at least one branched
polyol ester, which is obtained by reacting one or more polyhydric
alcohols with one or more branched mono-carboxylic acids containing
at least about 4 carbon atoms. The lubricating oil base stock is
present in an amount from about 30 to about 99.8 mass percent,
based on the total mass of the ashless lubricating oil.
[0011] This disclosure further relates in part to an ashless
lubricating oil having a composition comprising a lubricating oil
base stock as a major component; and at least one ashless antiwear
additive, as a minor component. The lubricating oil base stock is
at least one branched polyol ester, which is obtained by reacting
one or more polyhydric alcohols with one or more branched
mono-carboxylic acids containing at least about 4 carbon atoms. The
lubricating oil base stock is present in an amount from about 30 to
about 99.8 mass percent, based on the total mass of the ashless
lubricating oil.
[0012] This disclosure yet further relates in part to a method for
improving high temperature stability of a lubricating oil in an
engine or other mechanical component lubricated with the
lubricating oil by using as the lubricating oil an ashless
formulated oil. The ashless formulated oil has a composition
comprising a lubricating oil base stock as a major component, and a
mixture of (i) at least one ashless antiwear additive, (ii) at
least one ashless detergent, and (iii) at least one aminic
antioxidant, as minor components. The lubricating oil base stock is
at least one branched polyol ester, which is obtained by reacting
one or more polyhydric alcohols with one or more branched
mono-carboxylic acids containing at least about 4 carbon atoms. The
lubricating oil base stock is present in an amount from about 30 to
about 99.8 mass percent, based on the total mass of the lubricating
oil.
[0013] This disclosure also relates in part to a method for
improving high temperature stability of a lubricating oil in an
engine or other mechanical component lubricated with the
lubricating oil by using as the lubricating oil an ashless
formulated oil. The ashless formulated oil has a composition
comprising a lubricating oil base stock as a major component, and
at least one ashless antiwear additive, as a minor component. The
lubricating oil base stock is at least one branched polyol ester,
which is obtained by reacting one or more polyhydric alcohols with
one or more branched mono-carboxylic acids containing at least
about 4 carbon atoms. The lubricating oil base stock is present in
an amount from about 30 to about 99.8 mass percent, based on the
total mass of the lubricating oil.
[0014] It has been surprisingly found that, in accordance with this
disclosure, high temperature stability of a lubricating oil can be
attained in an engine or other mechanical component lubricated with
a lubricating oil by using as the lubricating oil an ashless
formulated oil having at least one branched polyol ester base
stock, in which the base stock is present in an amount from about
30 to about 99.8 mass percent, based on the total mass of the
lubricating oil. Such high temperature stability affords a number
of advantages including, for example, more compatibility with high
energy density engines equipped with turbo chargers, or DPFs or
GPFs, reducing engine cooling needs (smaller radiator or less wind
drag), and reducing water contamination (for engines equipped with
water injection technology).
[0015] In particular, it has been surprisingly found that the
ashless lubricating oils of this disclosure, in a bench Sequence
IIIE Screener test, reach 200% viscosity increase after 600 hours,
or after 800 hours, or after 1000 hours, or after 1100 hours
(versus about 300 hours for a typical synthetic engine oil as shown
in the Examples hereinbelow).
[0016] Other objects and advantages of the present disclosure will
become apparent from the detailed description that follows.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 shows lubricating oil formulations prepared in
accordance with the Examples, and also testing results from the
formulations.
[0018] FIG. 2 shows lubricating oil formulations prepared in
accordance with the Examples, and also testing results from the
formulations.
[0019] FIG. 3 shows lubricating oil formulations prepared in
accordance with Examples 13-16 and also testing results from the
formulations.
DETAILED DESCRIPTION
[0020] 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.
[0021] In accordance with this disclosure, it has been found that
engine lubricants with step-out oxidation stability can be
formulated. By improving the oxidation stability of the lubricants,
the deposit formation tendency on a metal surface is also reduced
significantly, enabling the use of ashless detergent additives.
Ashless antiwear additives, such as amine phosphates, have been
widely used in many industrial lubricants.
[0022] It has now been found that high temperature stability of a
lubricating oil can be attained in an engine or other mechanical
component lubricated with a lubricating oil by using as the
lubricating oil an ashless formulated oil having at least one
branched polyol ester base stock, in which the base stock is
present in an amount from about 30 to about 99.8 mass percent,
based on the total mass of the lubricating oil. The lubricating oil
preferably has a mixture of at least one ashless antiwear additive,
at least one ashless detergent, and at least one aminic
antioxidant. Such high temperature stability affords a number of
advantages including, for example, more compatibility with high
energy density engines equipped with turbo chargers, reducing
engine cooling needs (smaller radiator or less wind drag), and
reducing water contamination (for engines equipped with water
injection technology).
[0023] In addition, it has been found that improved oxidative
stability and deposit control can be attained in an engine or other
mechanical component lubricated with a lubricating oil by using as
the lubricating oil an ashless formulated oil having at least one
branched polyol ester base stock, in which the base stock is
present in an amount from about 30 to about 99.8 mass percent,
based on the total mass of the lubricating oil. The lubricating oil
preferably has a mixture of at least one ashless antiwear additive,
at least one ashless detergent, and at least one aminic
antioxidant.
Branched Polyol Ester Lubricating Oil Base Stocks
[0024] Branched polyol esters comprise a useful base stock of this
disclosure. The branched polyol esters are obtained by reacting one
or more polyhydric alcohols, preferably the hindered polyols (such
as the neopentyl polyols, e.g., neopentyl glycol, trimethylol
ethane, 2-methyl-2-propyl-1,3-propanediol, trimethylol propane,
pentaerythritol and dipentaerythritol) with single or mixed
branched mono-carboxylic acids containing at least about 4 carbon
atoms, preferably C.sub.5 to C.sub.30 branched mono-carboxylic
acids including 2,2-dimethyl propionic acid (neopentanoic acid),
neoheptanoic acid, neooctanoic acid, neononanoic acid, iso-hexanoic
acid, neodecanoic acid, 2-ethyl hexanoic acid (2EH),
3,5,5-trimethyl hexanoic acid (TMH), isoheptanoic acid, isooctanoic
acid, isononanoic acid, isodecanoic acid, or mixtures of any of
these materials. These branched polyol esters include fully
converted and partially converted polyol esters.
[0025] Particularly useful polyols include, for example, neopentyl
glycol, 2,2-dimethylol butane, trimethylol ethane, trimethylol
propane, trimethylol butane, mono-pentaerythritol, technical grade
pentaerythritol, di-pentaerythritol, tri-pentaerythritol, ethylene
glycol, propylene glycol and polyalkylene glycols (e.g.,
polyethylene glycols, polypropylene glycols, 1,4-butanediol,
sorbitol and the like, 2-methylpropanediol, polybutylene glycols,
etc., and blends thereof such as a polymerized mixture of ethylene
glycol and propylene glycol). The most preferred alcohols are
technical grade (e.g., approximately 88% mono-, 10% di- and 1-2%
tri-pentaerythritol) pentaerythritol, mono-pentaerythritol,
di-pentaerythritol, neopentyl glycol and trimethylol propane.
[0026] Particularly useful branched mono-carboxylic acids include,
for example, 2,2-dimethyl propionic acid (neopentanoic acid),
neoheptanoic acid, neooctanoic acid, neononanoic acid, iso-hexanoic
acid, neodecanoic acid, 2-ethyl hexanoic acid (2EH),
3,5,5-trimethyl hexanoic acid (TMH), isoheptanoic acid, isooctanoic
acid, isononanoic acid, isodecanoic acid, or mixtures of any of
these materials. One especially preferred branched acid is
3,5,5-trimethyl hexanoic acid. The term "neo" as used herein refers
to a trialkyl acetic acid, i.e., an acid which is triply
substituted at the alpha carbon with alkyl groups.
[0027] Preferably, the branched polyol ester is derived from a
polyhydric alcohol and a branched mono-carboxylic acid. In
particular, the branched polyol ester is obtained by reacting one
or more polyhydric alcohols with one or more branched
mono-carboxylic acids containing at least about 4 carbon atoms.
[0028] Preferred branched polyol esters useful in this disclosure
include, for example, mono-pentaerythritol ester of branched
mono-carboxylic acids, di-pentaerythritol ester of branched
mono-carboxylic acids, trimethylolpropane ester of C8-C10 acids,
and the like.
[0029] Other synthetic esters that can be useful in this disclosure
are those which are obtained by reacting one or more polyhydric
alcohols, preferably the hindered polyols (such as the neopentyl
polyols, e.g., neopentyl glycol, trimethylol ethane,
2-methyl-2-propyl-1,3-propanediol, trimethylol propane,
pentaerythritol and dipentaerythritol) with mono caboxylic acids
containing at least about 4 carbon atoms, preferably branched
C.sub.5 to C.sub.30 acids including caprylic acid, capric acid,
lauric acid, myristic acid, palmitic acid, stearic acid, arachic
acid, and behenic acid, or the corresponding branched chain fatty
acids or unsaturated fatty acids such as oleic acid, or mixtures of
any of these materials.
[0030] Other ester base oils useful in this disclosure include
adipate esters. The dialkyl adipate ester is derived from adipic
acid and a branched alkyl alcohol.
[0031] Mixtures of branched polyol ester base stocks with other
lubricating oil base stocks (e.g., Groups I, II, III, IV and V base
stocks) may be useful in the lubricating oil formulations of this
disclosure.
[0032] The branched polyol ester can be present in an amount of
from about 30 to about 99.8 weight percent, or from about 35 to
about 95 weight percent, or from about 40 to about 90 weight
percent, or from about 45 to about 85 weight percent, or from about
50 to about 80 weight percent, or from about 55 to about 75 weight
percent, or from about 60 to about 70 weight percent, based on the
total weight of the formulated oil.
Ashless Antiwear Agents
[0033] In accordance with this disclosure, the lubricating engine
oils have at least one ashless antiwear additive selected from a
phosphorus-containing ashless antiwear additive, a
sulfur-containing ashless antiwear additive, and a
phosphorus/sulfur-containing ashless antiwear additive.
Illustrative ashless antiwear additives useful in this disclosure
include, for example, amine phosphates, thiophosphates,
dithiophosphates, amine salts of sulfurized phosphates, alkylated
triphenyl phosphorothionates (e.g., butylated triphenyl
phosphorothionate), and mixtures thereof, and the like. These
ashless antiwear additives can be obtained commercially from
suppliers such as BASF under the trade name Irgalube 353, Irgalube
349, Irgalube 875, Irgalube 232, and from Vanderbilt Chemicals, LLC
under the trade name Vanlube 9123, and from Dorf Ketal under the
trade name PX 3844.
[0034] In particular, the ashless antiwear additive can be a
phosphate ester or salt, in which the phosphate ester or salt may
be a monohydrocarbyl, dihydrocarbyl or a trihydrocarbyl phosphate,
wherein each hydrocarbyl group is saturated. In one embodiment,
each hydrocarbyl group independently contains from about 6 to about
30, or from about 8 up to about 20, or from about 8 up to about 12
carbons atoms.
[0035] A phosphate ester or salt is a phosphorus acid ester
prepared by reacting one or more phosphorus acid or anhydride with
a saturated alcohol. The phosphorus acid or anhydride is generally
an inorganic phosphorus reagent, such as phosphorus pentoxide,
phosphorus trioxide, phosphorus tetroxide, phosphorous acid,
phosphoric acid, phosphorus halide, lower phosphorus esters, or a
phosphorus sulfide, including phosphorus pentasulfide, and the
like. Lower phosphorus acid esters generally contain from 1 to
about 7 carbon atoms in each ester group. Alcohols used to prepare
the phosphorus acid esters or salts include saturated alcohols.
Examples of commercially available alcohols including hexanol,
heptanol, octanol, nonanol, decanol, and undecanol, and dodecanol,
and alcohol mixtures include Alfol 1218 (a mixture of synthetic,
primary, straight-chain alcohols containing 12 to 18 carbon atoms);
Alfol 20+ alcohols (mixtures of C18-C28 primary alcohols having
mostly C20 alcohols as determined by GLC
(gas-liquid-chromatography)); and Alfol22+ alcohols (C18-C28
primary alcohols containing primarily C22 alcohols). Alfol alcohols
are available from Continental Oil Company. Another example of a
commercially available alcohol mixture is Adol 60 (about 75% by
weight of a straight chain C22 primary alcohol, about 15% of a C20
primary alcohol and about 8% of C18 and C24 alcohols). The Adol
alcohols are marketed by Ashland Chemical. The preferred alcohol is
octanol or those with more carbon atoms.
[0036] A variety of mixtures of monohydric fatty alcohols derived
from naturally occurring triglycerides and ranging in chain length
from C8 to C18 are available from Procter & Gamble Company.
These mixtures contain various amounts of fatty alcohols containing
12, 14, 16, or 18 carbon atoms. For example, CO-1214 is a fatty
alcohol mixture containing 0.5% of C10 alcohol, 66.0% of C12
alcohol, 26.0% of C14 alcohol and 6.5% of C16 alcohol.
[0037] Another group of commercially available mixtures include the
"Neodol" products available from Shell Chemical Co. For example,
Neodol 23 is a mixture of C12 and C13 alcohols; Neodol 25 is a
mixture of C12 to C15 alcohols; and Neodol 45 is a mixture of C14
to C15 linear alcohols. The phosphate contains from about 14 to
about 18 carbon atoms in each hydrocarbyl group. The hydrocarbyl
groups of the phosphate are generally derived from a mixture of
fatty alcohols having from about 14 up to about 18 carbon atoms.
The hydrocarbyl phosphate may also be derived from a fatty vicinal
diol. Fatty vicinal diols include those available from Ashland Oil
under the general trade designation Adol 114 and Adol 158. The
former is derived from a straight chain alpha olefin fraction of
C11-C14, and the latter is derived from a C15-C18 fraction.
[0038] The phosphate salts may be prepared by reacting an acidic
phosphate ester with an amine compound or a metallic base to form
an amine or a metal salt. The amines may be monoamines or
polyamines. Useful amines include those amines disclosed in U.S.
Pat. No. 4,234,435.
[0039] The monoamines generally contain a hydrocarbyl group which
contains from 1 to about 30 carbon atoms, or from 1 to about 12, or
from 1 to about 6. Examples of primary monoamines useful in the
present disclosure include methylamine, ethylamine, propylamine,
butylamine, cyclopentylamine, cyclohexylamine, octylamine,
dodecylamine, allylamine, cocoamine, stearylamine, and laurylamine.
Examples of secondary monoamines include dimethylamine,
diethylamine, dipropylamine, dibutylamine, dicyclopentylamine,
dicyclohexylamine, methylbutylamine, ethylhexylamine, and the
like.
[0040] A useful amine is a fatty (C8-30) amine which includes
n-octylamine, n-decylamine, n-dodecylamine, n-tetradecylamine,
n-hexadecylamine, n-octadecylamine, oleyamine, etc. Also useful
fatty amines include commercially available fatty amines such as
"Armeen" amines (products available from Akzo Chemicals, Chicago,
Ill.), such Armeen C, Armeen O, Armeen OL, Armeen T, Armeen HT,
Armeen S and Armeen S D, wherein the letter designation relates to
the fatty group, such as coco, oleyl, tallow, or stearyl
groups.
[0041] Other useful amines include primary ether amines, such as
those represented by the formula, R''(OR') x NH2, wherein R' is a
divalent alkylene group having about 2 to about 6 carbon atoms; x
is a number from one to about 150, or from about one to about five,
or one; and R'' is a hydrocarbyl group of about 5 to about 150
carbon atoms. An example of an ether amine is available under the
name SURFAM.RTM. amines produced and marketed by Mars Chemical
Company, Atlanta, Ga. Preferred ether amines are exemplified by
those identified as SURFAM P14B (decyloxypropylamine), SURFAM P16A
(linear C16), SURFAM P17B (tridecyloxypropylamine). The carbon
chain lengths (i.e., C14, etc.) of the SURFAMS described above and
used hereinafter are approximate and include the oxygen ether
linkage.
[0042] An illustrative amine is a tertiary-aliphatic primary amine.
Generally, the aliphatic group, preferably an alkyl group, contains
from about 4 to about 30, or from about 6 to about 24, or from
about 8 to about 22 carbon atoms. Usually the tertiary alkyl
primary amines are monoamines the alkyl group is a hydrocarbyl
group containing from one to about 27 carbon atoms and R6 is a
hydrocarbyl group containing from 1 to about 12 carbon atoms. Such
amines are illustrated by tert-butylamine, tert-hexylamine,
1-methyl-1-amino-cyclohexane, tert-octylamine, tert-decylamine,
tert-dodecylamine, tert-tetradecylamine, tert-hexadecylamine,
tert-octadecylamine, tert-tetracosanylamine, and
tert-octacosanylamine. Mixtures of tertiary aliphatic amines may
also be used in preparing the phosphate salt. Illustrative of amine
mixtures of this type are "Primene 81R" which is a mixture of
C11-C14 tertiary alkyl primary amines and "Primene JMT" which is a
similar mixture of C18-C22 tertiary alkyl primary amines (both are
available from Rohm and Haas Company). The tertiary aliphatic
primary amines and methods for their preparation are known to those
of ordinary skill in the art.
[0043] Another illustrative amine is a heterocyclic polyamine. The
heterocyclic polyamines include aziridines, azetidines, azolidines,
tetra- and dihydropyridines, pyrroles, indoles, piperidines,
imidazoles, di- and tetra-hydroimidazoles, piperazines, isoindoles,
purines, morpholines, thiomorpholines, N-aminoalkylmorpholines,
N-aminoalkylthiomorpholines, N-aminoalkyl-piperazines,
N,N'-diaminoalkylpiperazines, azepines, azocines, azonines,
azecines and tetra-, di- and perhydro derivatives of each of the
above and mixtures of two or more of these heterocyclic amines.
Preferred heterocyclic amines are the saturated 5- and 6-membered
heterocyclic amines containing only nitrogen, oxygen and/or sulfur
in the hetero ring, especially the piperidines, piperazines,
thiomorpholines, morpholines, pyrrolidines, and the like.
Piperidine, aminoalkyl substituted piperidines, piperazine,
aminoalkyl substituted piperazines, morpholine, aminoalkyl
substituted morpholines, pyrrolidine, and aminoalkyl-substituted
pyrrolidines, are especially preferred. Usually the aminoalkyl
substituents are substituted on a nitrogen atom forming part of the
hetero ring. Specific examples of such heterocyclic amines include
N-aminopropylmorpholine, N-aminoethylpiperazine, and
N,N'-diaminoethylpiperazine. Hydroxy heterocyclic polyamines are
also useful. Examples include N-(2-hydroxyethyl)cyclohexylamine,
3-hydroxycyclopentylamine, parahydroxyaniline,
N-hydroxyethylpiperazine, and the like.
[0044] Ashless antiwear additives also may include a fatty
imidazoline or a reaction product of a fatty carboxylic acid and at
least one polyamine. The fatty imidazoline has fatty substituents
containing from 8 to about 30, or from about 12 to about 24 carbon
atoms. The substituent may be saturated or unsaturated,
heptadeceneyl derived oleyl groups, preferably saturated. In one
aspect, the fatty imidazoline may be prepared by reacting a fatty
carboxylic acid with a polyalkylenepolyamine, such as those
discussed above. The fatty carboxylic acids are generally mixtures
of straight and branched chain fatty carboxylic acids containing
about 8 to about 30 carbon atoms, or from about 12 to about 24, or
from about 16 to about 18. Carboxylic acids include the
polycarboxylic acids or carboxylic acids or anhydrides having from
2 to about 4 carbonyl groups, preferably 2. The polycarboxylic
acids include succinic acids and anhydrides and Diels-Alder
reaction products of unsaturated monocarboxylic acids with
unsaturated carboxylic acids (such as acrylic, methacrylic, maleic,
fumaric, crotonic and itaconic acids). Preferably, the fatty
carboxylic acids are fatty monocarboxylic acids, having from about
8 to about 30, preferably about 12 to about 24 carbon atoms, such
as octanoic, oleic, stearic, linoleic, dodecanoic, and tall oil
acids, preferably stearic acid. The fatty carboxylic acid is
reacted with at least one polyamine. The polyamines may be
aliphatic, cycloaliphatic, heterocyclic or aromatic. Examples of
the polyamines include alkylene polyamines and heterocyclic
polyamines.
[0045] Hydroxyalkyl groups are to be understood as meaning, for
example, monoethanolamine, diethanolamine or triethanolamine, and
the term amine also includes diamine. The amine used for the
neutralization depends on the phosphoric esters used. The ashless
antiwear additive according to the disclosure has the following
advantages. It very high effectiveness when used in low
concentrations and it is free of chlorine. For the neutralization
of the phosphoric esters, the latter are taken and the
corresponding amine slowly added with stirring. The resulting heat
of neutralization is removed by cooling. The ashless antiwear
additive according to the disclosure can be incorporated into the
respective base liquid with the aid of fatty substances (e.g. tall
oil fatty acid, oleic acid, etc.) as solubilizers. The base liquids
used are napthenic or paraffinic base oils, synthetic oils (e.g.
polyglycols, mixed polyglycols), polyolefins, carboxylic esters,
and the like.
[0046] The ashless antiwear additive can include at least one
straight and/or branched chain saturated or unsaturated
monocarboxylic acid which is optionally sulphurized in an amount
which may be up to 35% by weight; and/or an ester of such an acid.
At least one triazole or alkyl derivatives thereof, or short chain
alkyl of up to 5 carbon atoms and is hydrogen, morphilino, alkyl,
amido, amino, hydroxy or alkyl or aryl substituted derivatives
thereof; or a triazole selected from 1,2,4 triazole, 1,2,3
triazole, 3-amino-1,2,4 triazole,
1-H-benzotriazole-1-yl-methylisocyanide,
methylene-bis-benzotriazole and naphthotriazole. The neutral
organic phosphate which forms a component of the formulation may be
present in an amount of 0.01 to 4%, preferably 1.5 to 2.5% by
weight of the composition. The above amine phosphates and any of
the aforementioned benzo- or tolyltriazoles can be mixed together
to form a single component capable of delivering antiwear
performance. The neutral organic phosphate is also a conventional
ingredient of lubricating compositions and any such neutral organic
phosphate falling within the formula as previously defined may be
employed.
[0047] In an embodiment, phosphates for use in the present
disclosure include phosphates, acid phosphates, phosphites and acid
phosphites. The phosphates include triaryl phosphates, trialkyl
phosphates, trialkylaryl phosphates, triarylalkyl phosphates and
trialkenyl phosphates. As specific examples of these, referred to
are triphenyl phosphate, tricresyl phosphate, benzyldiphenyl
phosphate, ethyldiphenyl phosphate, tributyl phosphate,
ethyldibutyl phosphate, cresyldiphenyl phosphate, dicresylphenyl
phosphate, ethylphenyldiphenyl phosphate, diethylphenylphenyl
phosphate, propylphenyldiphenyl phosphate, dipropylphenylphenyl
phosphate, triethylphenyl phosphate, tripropylphenyl phosphate,
butylphenyldiphenyl phosphate, dibutylphenylphenyl phosphate,
tributylphenyl phosphate, trihexyl phosphate, tri(2-ethylhexyl)
phosphate, tridecyl phosphate, trilauryl phosphate, trimyristyl
phosphate, tripalmityl phosphate, tristearyl phosphate, and
trioleyl phosphate. The acid phosphates include, for example,
2-ethylhexyl acid phosphate, ethyl acid phosphate, butyl acid
phosphate, oleyl acid phosphate, tetracosyl acid phosphate,
isodecyl acid phosphate, lauryl acid phosphate, tridecyl acid
phosphate, stearyl acid phosphate, and isostearyl acid
phosphate.
[0048] The phosphites include, for example, triethyl phosphite,
tributyl phosphite, triphenyl phosphite, tricresyl phosphite,
tri(nonylphenyl) phosphite, tri(2-ethylhexyl) phosphite, tridecyl
phosphite, trilauryl phosphite, triisooctyl phosphite,
diphenylisodecyl phosphite, tristearyl phosphite, and trioleyl
phosphite.
[0049] The acid phosphites include, for example, dibutyl
hydrogenphosphite, dilauryl hydrogenphosphite, dioleyl
hydrogenphosphite, distearyl hydrogenphosphite, and diphenyl
hydrogenphosphite.
[0050] Amines that form amine salts with such phosphates include,
for example, mono-substituted amines, di-substituted amines and
tri-substituted amines.
[0051] Examples of the mono-substituted amines include butylamine,
pentylamine, hexylamine, cyclohexylamine, octylamine, laurylamine,
stearylamine, oleylamine and benzylamine; and those of the
di-substituted amines include dibutylamine, dipentylamine,
dihexylamine, dicyclohexylamine, dioctylamine, dilaurylamine,
distearylamine, dioleylamine, dibenzylamine, stearyl
monoethanolamine, decyl monoethanolamine, hexyl monopropanolamine,
benzyl monoethanolamine, phenyl monoethanolamine, and tolyl
monopropanolamine. Examples of tri-substituted amines include
tributylamine, tripentylamine, trihexylamine, tricyclohexylamine,
trioctylamine, trilaurylamine, tristearylamine, trioleylamine,
tribenzylamine, dioleyl monoethanolamine, dilauryl
monopropanolamine, dioctyl monoethanolamine, dihexyl
monopropanolamine, dibutyl monopropanolamine, oleyl diethanolamine,
stearyl dipropanolamine, lauryl diethanolamine, octyl
dipropanolamine, butyl diethanolamine, benzyl diethanolamine,
phenyl diethanolamine, tolyl dipropanolamine, xylyl diethanolamine,
triethanolamine, and tripropanolamine.
[0052] As used herein, the term "hydrocarbyl substituent" or
"hydrocarbyl group" is used in its ordinary sense, which is
well-known to those skilled in the art. Specifically, it refers to
a group having a carbon atom directly attached to the remainder of
the molecule and having predominantly hydrocarbon character.
Examples of hydrocarbyl groups include: hydrocarbon substituents,
that is, aliphatic (e.g., alkyl or alkenyl), alicyclic (e.g.,
cycloalkyl, cycloalkenyl) substituents, and aromatic-, aliphatic-,
and alicyclic-substituted aromatic substituents, as well as cyclic
substituents wherein the ring is completed through another portion
of the molecule (e.g., two substituents together form an alicyclic
radical); the substituted hydrocarbon substituents, that is,
substituents containing non-hydrocarbon groups which, in the
context of this disclosure, do not alter the predominantly
hydrocarbon substituent, hydroxy, alkoxy, nitro); hetero-atom
containing substituents, that is, substituents which, while having
a predominantly hydrocarbon character, in the context of this
disclosure, contain other than carbon in a ring or chain otherwise
composed of carbon atoms. Heteroatoms include sulfur, oxygen,
nitrogen, and encompass substituents as pyridyl, furyl, thienyl and
imidazolyl. In general, no more than two, preferably no more than
one, non-hydrocarbon substituent will be present for every ten
carbon atoms in the hydrocarbyl group; typically, there will be no
non-hydrocarbon substituents in the hydrocarbyl group.
[0053] Examples of straight chain hydrocarbyl groups include
methyl, ethyl, n-propyl, n-butyl, n-hexyl, n-octyl, n-decyl,
n-dodecyl, n-tetradecyl, stearyl, n-hexadecyl, n-octadecyl, oleyl,
and cetyl. Examples of branched-chain hydrocarbon groups include
isopropyl, isobutyl, secondary butyl, tertiary butyl, neopentyl,
2-ethylhexyl, and 2,6-dimethylheptyl. Examples of cyclic groups
include cyclobutyl, cyclopentyl, methylcyclopentyl, cyclohexyl,
methylcyclohexyl, cycloheptyl, and cyclooctyl. A few examples of
aromatic hydrocarbyl groups and mixed aromatic-aliphatic
hydrocarbyl groups include phenyl, methylphenyl, tolyl, and
naphthyl.
[0054] The substituent groups can also comprise a mixture of
hydrocarbyl groups derived from commercial alcohols. Examples of
some monohydric alcohols and alcohol mixtures include the
commercially available "Alfol.TM." alcohols marketed by Continental
Oil Corporation. Alfol.TM. 810, for instance, is a mixture
containing alcohols consisting essentially of straight chain,
primary alcohols having from 8 to 12 carbon atoms. Alfol.TM. 12 is
a mixture of mostly C12 fatty alcohols; Alfol.TM. 22+ comprises C
18-28 primary alcohols having mostly C 22 alcohols, and so on.
Various mixtures of monohydric fatty alcohols derived from
naturally occurring triglycerides and ranging in chain length from
C8 to C18 are available from Procter & Gamble Company.
"Neodol.TM." alcohols are available from Shell Chemical Co., where,
for instance, Neodol.TM. 25 is a mixture of C 12 to C 15
alcohols.
[0055] In an embodiment, the phosphorus compounds useful in the
present disclosure are prepared by well known reactions. One route
the reaction of an alcohol or a phenol with phosphorus trichloride
or by a transesterification reaction. Alcohols and phenols can be
reacted with phosphorus pentoxide to provide a mixture of an alkyl
or aryl phosphoric acid and a dialkyl or diaryl phosphoric acid.
Alkyl phosphates can also be prepared by the oxidation of the
corresponding phosphites. In any case, the reaction can be
conducted with moderate heating. Moreover, various phosphorus
esters can be prepared by reaction using other phosphorus esters as
starting materials. Thus, medium chain (C8 to C22) phosphorus
esters have been prepared by reaction of dimethylphosphite with a
mixture of medium-chain alcohols by means of a thermal
transesterification or an acid- or base-catalyzed
transesterification; see for example U.S. Pat. No. 4,652,416. Most
such materials are also commercially available; for instance,
triphenyl phosphite is available from Albright and Wilson as
Duraphos TPP.TM.; di-n-butyl hydrogen phosphite from Albright and
Wilson as Duraphos DBHP.TM.; and triphenylthiophosphate from BASF
as Irgalube TPPT.TM..
[0056] Organic triesters of phosphorus acids are also employed as
ashless antiwear additives. Typical esters include
triarylphosphates, trialkyl phosphates, neutral alkylaryl
phosphates, alkoxyalkyl phosphates, triaryl phosphite,
trialkylphosphite, neutral alkyl aryl phosphites, neutral
phosphonate esters and neutral phosphine oxide esters. In one
embodiment, the long chain dialkyl phosphonate esters are used.
More preferentially, the dimethyl-, diethyl-, and dipropyl-oleyl
phophonates can be used. Neutral acids of phosphorus acids are the
triesters rather than an acid (HO--P) or a salt of an acid.
[0057] Any C4 to C8 alkyl or higher phosphate ester may be employed
in the disclosure. For example, tributyl phosphate (TBP) and tri
isooctal phosphate (TOF) can be used. The specific triphosphate
ester or combination of esters can easily be selected by one
skilled in the art to adjust the density, viscosity etc. of the
formulated fluid. Mixed esters, such as dibutyl octyl phosphate or
the like may be employed rather than a mixture of two or more
trialkyl phosphates.
[0058] A trialkyl phosphate is useful as an ashless antiwear
additive and to adjust the specific gravity of the formulation, but
it is desirable that the specific trialkyl phosphate be a liquid at
low temperatures. Consequently, a mixed ester containing at least
one partially alkylated with a C3 to C4 alkyl group is very
desirable, for example, 4-isopropylphenyl diphenyl phosphate or
3-butylphenyl diphenyl phosphate. Even more desirable is a triaryl
phosphate produced by partially alkylating phenol with butylene or
propylene to form a mixed phenol which is then reacted with
phosphorus oxychloride as taught in U.S. Pat. No. 3,576,923.
[0059] Any mixed triaryl phosphate (TAP) esters may be used as
ashless antiwear additives including cresyl diphenyl phosphate,
tricresyl phosphate, mixed xylyl cresyl phosphates, lower
alkylphenyl/phenyl phosphates, such as mixed isopropylphenyl/phenyl
phosphates, t-butylphenyl phenyl phosphates.
[0060] The phosphoric acid ester, thiophosphoric acid ester, and
amine salt thereof functions to enhance the lubricating
performances, and can be selected from known compounds
conventionally employed as ashless antiwear additives. Generally
employed are phosphoric acid esters, or an amine salt thereof which
has an alkyl group, an alkenyl group, an alkylaryl group, or an
aralkyl group, any of which contains approximately 3 to 30 carbon
atoms.
[0061] In an embodiment, examples of the phosphoric acid esters
include aliphatic phosphoric acid esters such as triisopropyl
phosphate, tributyl phosphate, ethyl dibutyl phosphate, trihexyl
phosphate, tri-2-ethylhexyl phosphate, trilauryl phosphate,
tristearyl phosphate, and trioleyl phosphate; and aromatic
phosphoric acid esters such as benzyl phenyl phosphate, allyl
diphenyl phosphate, triphenyl phosphate, tricresyl phosphate, ethyl
diphenyl phosphate, cresyl diphenyl phosphate, dicresyl phenyl
phosphate, ethylphenyl diphenyl phosphate, diethylphenyl phenyl
phosphate, propylphenyl diphenyl phosphate, dipropylphenyl phenyl
phosphate, triethylphenyl phosphate, tripropylphenyl phosphate,
butylphenyl diphenyl phosphate, dibutylphenyl phenyl phosphate, and
tributylphenyl phosphate. Preferably, the phosphoric acid ester is
a trialkylphenyl phosphate.
[0062] Also employable are amine salts of the above-mentioned
phosphates. Amine salts of acidic alkyl or aryl esters of the
phosphoric acid and thiophosphoric acid are also employable.
Preferably, the amine salt is an amine salt of trialkylphenyl
phosphate or an amine salt of alkyl phosphate.
[0063] One or any combination of the compounds selected from the
group consisting of a phosphoric acid ester, and an amine salt
thereof may be used.
[0064] The phosphorus acid ester and/or its amine salt function as
ashless antiwear additives and to enhance the lubricating
performances, and can be selected from known compounds
conventionally employed as ashless antiwear additives. Generally
employed are a phosphorus acid ester or an amine salt thereof which
has an alkyl group, an alkenyl group, an alkylaryl group, or an
aralkyl group, any of which contains approximately 3 to 30 carbon
atoms.
[0065] In another embodiment, examples of the phosphorus acid
esters include aliphatic phosphorus acid esters such as
triisopropyl phosphite, tributyl phosphite, ethyl dibutyl
phosphite, trihexyl phosphite, tri-2-ethylhexylphosphite, trilauryl
phosphite, tristearyl phosphite, and trioleyl phosphite; and
aromatic phosphorus acid esters such as benzyl phenyl phosphite,
allyl diphenylphosphite, triphenyl phosphite, tricresyl phosphite,
ethyl diphenyl phosphite, tributyl phosphite, ethyl dibutyl
phosphite, cresyl diphenyl phosphite, dicresyl phenyl phosphite,
ethylphenyl diphenyl phosphite, diethylphenyl phenyl phosphite,
propylphenyl diphenyl phosphite, dipropylphenyl phenyl phosphite,
triethylphenyl phosphite, tripropylphenyl phosphite, butylphenyl
diphenyl phosphite, dibutylphenyl phenyl phosphite, and
tributylphenyl phosphite. Also favorably employed are dilauryl
phosphite, dioleyl phosphite, dialkyl phosphites, and diphenyl
phosphite. Preferably, the phosphorus acid ester is a dialkyl
phosphite or a trialkyl phosphite.
[0066] In an embodiment, the phosphate salt may be derived from a
polyamine. The polyamines include alkoxylated diamines, fatty
polyamine diamines, alkylenepolyamines, hydroxy containing
polyamines, condensed polyamines arylpolyamines, and heterocyclic
polyamines. Commercially available examples of alkoxylated diamines
include those amine where y in the above formula is one. Examples
of these amines include Ethoduomeen T/13 and T/20 which are
ethylene oxide condensation products of N-tallowtrimethylenediamine
containing 3 and 10 moles of ethylene oxide per mole of diamine,
respectively.
[0067] In another embodiment, the polyamine is a fatty diamine. The
fatty diamines include mono- or dialkyl, symmetrical or
asymmetrical ethylene diamines, propane diamines (1,2, or 1,3), and
polyamine analogs of the above. Suitable commercial fatty
polyamines are Duomeen C. (N-coco-1,3-diaminopropane), Duomeen S
(N-soya-1,3-diaminopropane), Duomeen T
(N-tallow-1,3-diaminopropane), and Duomeen O
(N-oleyl-1,3-diaminopropane). "Duomeens" are commercially available
from Armak Chemical Co., Chicago, Ill.
[0068] Such alkylenepolyamines include methylenepolyamines,
ethylenepolyamines, butylenepolyamines, propylenepolyamines,
pentylenepolyamines, etc. The higher homologs and related
heterocyclic amines such as piperazines and N-amino
alkyl-substituted piperazines are also included. Specific examples
of such polyamines are ethylenediamine, triethylenetetramine,
tris-(2-aminoethyl)amine, propylenediamine, trimethylenediamine,
tripropylenetetramine, tetraethylenepentamine,
hexaethyleneheptamine, pentaethylenehexamine, etc. Higher homologs
obtained by condensing two or more of the above-noted
alkyleneamines are similarly useful as are mixtures of two or more
of the aforedescribed polyamines.
[0069] In one embodiment, the polyamine is an ethylenepolyamine.
Such polyamines are described in detail under the heading Ethylene
Amines in Kirk Othmer's "Encyclopedia of Chemical Technology", 2d
Edition, Vol. 7, pages 22-37, Interscience Publishers, New York
(1965). Ethylenepolyamines are often a complex mixture of
polyalkylenepolyamines including cyclic condensation products.
[0070] Other useful types of polyamine mixtures are those resulting
from stripping of the above-described polyamine mixtures to leave,
as residue, what is often termed "polyamine bottoms". In general,
alkylenepolyamine bottoms can be characterized as having less than
2%, usually less than 1% (by weight) material boiling below about
200 C. A typical sample of such ethylene polyamine bottoms obtained
from the Dow Chemical Company of Freeport, Tex. designated "E-100".
These alkylenepolyamine bottoms include cyclic condensation
products such as piperazine and higher analogs of
diethylenetriamine, triethylenetetramine and the like. These
alkylenepolyamine bottoms can be reacted solely with the acylating
agent or they can be used with other amines, polyamines, or
mixtures thereof.
[0071] Another useful polyamine is a condensation reaction between
at least one hydroxy compound with at least one polyamine reactant
containing at least one primary or secondary amino group. The
hydroxy compounds are preferably polyhydric alcohols and amines.
The polyhydric alcohols are described below. (See carboxylic ester
dispersants.) In one embodiment, the hydroxy compounds are
polyhydric amines. Polyhydric amines include any of the
above-described monoamines reacted with an alkylene oxide (e.g.,
ethylene oxide, propylene oxide, butylene oxide, etc.) having from
two to about 20 carbon atoms, or from two to about four. Examples
of polyhydric amines include tri-(hydroxypropyl)amine,
tris-(hydroxymethyl)amino methane,
2-amino-2-methyl-1,3-propanediol,
N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine, and
N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine, preferably
tris(hydroxymethyl)aminomethane (THAM).
[0072] Polyamines which react with the polyhydric alcohol or amine
to form the condensation products or condensed amines, are
described above. Preferred polyamines include triethylenetetramine
(TETA), tetraethylenepentamine (TEPA), pentaethylenehexamine
(PEHA), and mixtures of polyamines such as the above-described
"amine bottoms".
[0073] Preferred ashless antiwear additives selected from
phosphorus-containing ashless antiwear additives, sulfur-containing
ashless antiwear additives, and phosphorus/sulfur-containing
ashless antiwear additives useful in this disclosure include, for
example, amine phosphates, thiophosphates, dithiophosphates, amine
salts of sulfurized phosphates, and mixtures thereof, and the
like.
[0074] The concentration of ashless antiwear additive selected from
a phosphorus-containing ashless antiwear additive, a
sulfur-containing ashless antiwear additive, and a
phosphorus/sulfur-containing ashless antiwear additive in the
lubricating oils of this disclosure can range from 0.05 to 4.0
weight percent, preferably 0.1 to 2.0 weight percent, and more
preferably from 0.2 weight percent to 1.0 weight percent, based on
the total weight of the lubricating oil.
Ashless Detergents
[0075] Illustrative ashless detergents useful in this disclosure
include, for example, nonionic detergents such as polyoxyethylene,
polyoxypropylene, or polyoxybutylene alkyl ethers. For reference,
see "Nonionic Surfactants: Physical Chemistry" Martin J. Schick,
CRC Press; 2 edition (Mar. 27, 1987). These ashless detergents are
less common in engine lubricant formulations, but offer a number of
advantages such as improved solubility in ester base oils.
[0076] The preferred ashless detergents of this disclosure include
ashless detergents soluble in a branched polyol ester, preferably a
mono- or dipentaerythritol ester of at least one branched mono
carboxylic acid, and more preferably the nonionic detergents.
[0077] The ashless detergent concentration in the lubricating oils
of this disclosure can range from 0.5 to 6.0 weight percent,
preferably 0.6 to 5.0 weight percent, and more preferably from 0.8
weight percent to 4.0 weight percent, based on the total weight of
the lubricating oil.
[0078] As used herein, the detergent concentrations are given on an
"as delivered" basis. Typically, the active detergent is delivered
with a process oil. The "as delivered" detergent typically contains
from 20 weight percent to 100 weight percent, or from 40 weight
percent to 60 weight percent, of active detergent in the "as
delivered" detergent product.
Amine Antioxidants
[0079] 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.
[0080] Useful antioxidants include amine antioxidants, preferably
aromatic amine antioxidants. Aromatic amine antioxidants may be
used alone or in combination with phenolic antioxidants. Typical
examples of amine 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)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 20 carbon atoms, and preferably
contains from 6 to 12 carbon atoms. The aliphatic group is an
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.
[0081] Typical aromatic amine antioxidants have alkyl substituent
groups of at least 6 carbon atoms. Examples of aliphatic groups
include hexyl, heptyl, octyl, nonyl, and decyl. Generally, the
aliphatic groups will not contain more than 14 carbon atoms. The
general types of amine antioxidants useful in the present
compositions include diphenylamines, phenyl naphthylamines,
phenothiazines, 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-alpha-naphthylamine; and
p-octylphenyl-alpha-naphthylamine. Polymeric aminic antioxidants
derived from these diphenylamines, phenyl naphthylamines, and their
mixtures can also be used. The polymeric aminic antioxidants may be
available in a concentrate from with active polymeric amines in the
10 to 40 weight %. These polymeric aminic antioxidant concentrates
are commercially available from, for example, Nyco S. A., under the
trade name of Nycoperf AO 337, which is a concentrate containing
approximately 3 weight percent active polymeric aminic
antioxidant
[0082] Preferred antioxidants include arylamines and polymeric
aminic antioxidants. The arylamines antioxidants may be used
individually or in combination. Such additives may be used in an
amount of 0.01 to 5 weight percent, preferably 0.01 to 1.5 weight
percent, more preferably zero to less than 1.5 weight percent, more
preferably zero to less than 1 weight percent. The polymeric aminic
antioxidant concentrates may be used in an amount of 1 to 15 weight
percent, preferably 7 to 13 weight percent.
[0083] The preferred amine antioxidants in this disclosure include
polymeric or oligomeric amines which are the polymerization
reaction products of one or more substituted or
hydrocarbyl-substituted diphenyl amities, one or more unsubstituted
or hydrocarbyl-substituted phenyl naphthyl amines, or both one or
more of unsubstituted or hydrocarbyl-substituted diphenylamine with
one or more unsubstituted or hydrocarbyl-substituted phenyl
naphthylamine. A representative schematic is presented below:
wherein (a) and (b) each range from zero to 10, preferably zero to
5, more preferably zero to 3, most preferably 1 to 3, provided
(a)+(b) is at least 2; for example:
##STR00001##
wherein R.sup.2 is a styrene or C.sub.1 to C.sub.30 alkyl, R.sup.3
is a styrene or C.sub.1 to C.sub.30 alkyl, R.sup.4 is a styrene or
C.sub.1 to C.sub.30 alkyl, preferably R2 is a C.sub.1 to C.sub.30
alkyl, R3 is a C.sub.1 to C.sub.30 alkyl, R4 is a C.sub.1 to
C.sub.30 alkyl, more preferably R2 is a C.sub.4 to C.sub.10 alkyl,
R3 is a C.sub.4 to C.sub.10 alkyl and R4 is a C.sub.4 to C.sub.10
alkyl, p, q and y individually range from 0 to up to the valence of
the aryl group to which the respective R groups are attached,
preferably at least one of p, q and y range from 1 to up to the
valence of the aryl group to which the respective R group(s) are
attached, more preferably p, q and y each individually range from
at least 1 to up to the valence of the aryl group to which the
respective R groups are attached.
[0084] Other more extensive oligomers are within the scope of this
disclosure, but materials of formulae A, B, C and D are preferred.
Examples can be also found in U.S. Pat. No. 8,492,321, which is
herein incorporated by reference.
Other Lubricating Oil Base Stocks
[0085] A wide range of lubricating base oils is known in the art.
Lubricating base oils that are useful in the present disclosure are
both natural oils, and synthetic oils, and unconventional oils (or
mixtures thereof) can be used unrefined, refined, or rerefined (the
latter is also known as reclaimed or reprocessed oil). Unrefined
oils are those obtained directly from a natural or synthetic source
and used without added purification. These include shale oil
obtained directly from retorting operations, petroleum oil obtained
directly from primary distillation, and ester oil obtained directly
from an esterification process. Refined oils are similar to the
oils discussed for unrefined oils except refined oils are subjected
to one or more purification steps to improve at least one
lubricating oil property. One skilled in the art is familiar with
many purification processes. These processes include solvent
extraction, secondary distillation, acid extraction, base
extraction, filtration, and percolation. Rerefined oils are
obtained by processes analogous to refined oils but using an oil
that has been previously used as a feed stock.
[0086] 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 TABLE 1 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
[0087] 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.
[0088] Group II and/or Group III hydroprocessed or hydrocracked
base stocks, including synthetic oils such as polyalphaolefins,
alkyl aromatics and synthetic esters are also well known base stock
oils.
[0089] 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.
[0090] 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-hexene, 1-octene, 1-decene,
1-dodecene and the like, being preferred. The preferred
polyalphaolefins are poly-1-hexene, poly-1-octene, poly-1-decene
and poly-1-dodecene and mixtures thereof and mixed olefin-derived
polyolefins. However, the dimers of higher olefins in the range of
C.sub.14 to C.sub.18 may be used to provide low viscosity base
stocks of acceptably low volatility. Depending on the viscosity
grade and the starting oligomer, the PAOs may be predominantly
trimers and tetramers of the starting olefins, with minor amounts
of the higher oligomers, having a viscosity range of 1.5 to 12 cSt.
PAO fluids of particular use may include 3.0 cSt, 3.4 cSt, and/or
3.6 cSt and combinations thereof. Bi-modal mixtures of PAO fluids
having a viscosity range of 1.5 to 150 cSt may be used if
desired.
[0091] The PAO fluids may be conveniently made by the
polymerization of an alphaolefin in the presence of a
polymerization catalyst such as the Friedel-Crafts catalysts
including, for example, aluminum trichloride, boron trifluoride or
complexes of boron trifluoride with water, alcohols such as
ethanol, propanol or butanol, carboxylic acids or esters such as
ethyl acetate or ethyl propionate. For example the methods
disclosed by U.S. Pat. No. 4,149,178 or 3,382,291 may be
conveniently used herein. Other descriptions of PAO synthesis are
found in the following U.S. Pat. Nos. 3,742,082; 3,769,363;
3,876,720; 4,239,930; 4,367,352; 4,413,156; 4,434,408; 4,910,355;
4,956,122; and 5,068,487. The dimers of the C.sub.14 to Cis olefins
are described in U.S. Pat. No. 4,218,330.
[0092] The alkylated naphthalene can be used as base oil or base
oil component and can be any hydrocarbyl molecule that contains at
least about 5% of its weight derived from a naphthenoid moiety, or
its derivatives. These alkylated naphthalenes include alkyl
naphthalenes, alkyl naphthols, and the like. The naphthenoid group
can be mono-alkylated, dialkylated, polyalkylated, and the like.
The naphthenoid group can be mono- or poly-functionalized. The
naphthenoid group can also be derived from natural (petroleum)
sources, provided at least about 5% of the molecule is comprised of
the naphthenoid moiety. Viscosities at 100.degree. C. of
approximately 3 cSt to about 50 cSt are preferred, with viscosities
of approximately 3.4 cSt to about 20 cSt often being more preferred
for the naphthylene component. In one embodiment, an alkyl
naphthalene where the alkyl group is primarily comprised of
1-hexadecene is used. Other alkylates of naphthalene 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.
[0093] Alkylated naphthalenes 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 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.
[0094] Mixtures of alkylated naphthalene base stocks with other
lubricating oil base stocks (e.g., Groups I, II, III, IV and V base
stocks) may be useful in the lubricating oil formulations of this
disclosure.
[0095] The alkylated naphthalene can be present in an amount of
from about 30 to about 99.8 weight percent, or from about 35 to
about 95 weight percent, or from about 40 to about 90 weight
percent, or from about 45 to about 85 weight percent, or from about
50 to about 80 weight percent, or from about 55 to about 75 weight
percent, or from about 60 to about 70 weight percent, based on the
total weight of the formulated oil.
[0096] 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.
[0097] Gas-to-Liquids (GTL) base oils, Fischer-Tropsch wax derived
base oils, and other wax-derived hydroisomerized (wax isomerate)
base oils be advantageously used in the instant disclosure, and may
have useful kinematic viscosities at 100.degree. C. of about 3 cSt
to about 50 cSt, preferably about 3 cSt to about 30 cSt, more
preferably about 3.5 cSt to about 25 cSt, as exemplified by GTL 4
with kinematic viscosity of about 4.0 cSt at 100.degree. C. and a
viscosity index of about 141. These Gas-to-Liquids (GTL) base oils,
Fischer-Tropsch wax derived base oils, and other wax-derived
hydroisomerized base oils may have useful pour points of about
-20.degree. C. or lower, and under some conditions may have
advantageous pour points of about -25.degree. C. or lower, with
useful pour points of about -30.degree. C. to about -40.degree. C.
or lower. Useful compositions of Gas-to-Liquids (GTL) base oils,
Fischer-Tropsch wax derived base oils, and wax-derived
hydroisomerized base oils are recited in U.S. Pat. Nos. 6,080,301;
6,090,989, and 6,165,949 for example, and are incorporated herein
in their entirety by reference.
[0098] The hydrocarbyl aromatics can be used as base oil or base
oil component and can be any hydrocarbyl molecule that contains at
least about 5% of its weight derived from an aromatic moiety such
as a benzenoid moiety or naphthenoid moiety, or their derivatives.
These hydrocarbyl aromatics include alkyl benzenes, alkyl
naphthalenes, alkyl diphenyl oxides, alkyl naphthols, alkyl
diphenyl sulfides, alkylated bis-phenol A, alkylated thiodiphenol,
and the like. The aromatic can be mono-alkylated, dialkylated,
polyalkylated, and the like. The aromatic can be mono- or
poly-functionalized. The hydrocarbyl groups can also be comprised
of mixtures of alkyl groups, alkenyl groups, alkynyl, cycloalkyl
groups, cycloalkenyl groups and other related hydrocarbyl groups.
The hydrocarbyl groups can range from about C.sub.6 up to about
C.sub.60 with a range of about C.sub.8 to about C.sub.20 often
being preferred. A mixture of hydrocarbyl groups is often
preferred, and up to about three such substituents may be present.
The hydrocarbyl group can optionally contain sulfur, oxygen, and/or
nitrogen containing substituents. The aromatic group can also be
derived from natural (petroleum) sources, provided at least about
5% of the molecule is comprised of an above-type aromatic moiety.
Viscosities at 100.degree. C. of approximately 3 cSt to about 50
cSt are preferred, with viscosities of approximately 3.4 cSt to
about 20 cSt often being more preferred for the hydrocarbyl
aromatic component. In one embodiment, an alkyl naphthalene where
the alkyl group is primarily comprised of 1-hexadecene is used.
Other alkylates of aromatics can be advantageously used.
Naphthalene or methyl naphthalene, for example, can be alkylated
with olefins such as octene, decene, dodecene, tetradecene or
higher, mixtures of similar olefins, and the like. Useful
concentrations of hydrocarbyl aromatic in a lubricant oil
composition can be about 2% to about 25%, preferably about 4% to
about 20%, and more preferably about 4% to about 15%, depending on
the application.
[0099] 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.
[0100] 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.
[0101] 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.
[0102] 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.
[0103] GTL base stock(s) and/or base oil(s) derived from GTL
materials, especially, hydrodewaxed or hydroisomerized/followed by
cat and/or solvent dewaxed wax or waxy feed, preferably F-T
material derived base stock(s) and/or base oil(s), are
characterized typically as having kinematic viscosities at
100.degree. C. of from about 2 mm.sup.2/s to about 50 mm.sup.2/s
(ASTM D445). They are further characterized typically as having
pour points of -5.degree. C. to about -40.degree. C. or lower (ASTM
D97). They are also characterized typically as having viscosity
indices of about 80 to about 140 or greater (ASTM D2270).
[0104] 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 phosphorous and aromatics make this
materially especially suitable for the formulation of low SAP
products.
[0105] 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.
[0106] 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).
[0107] 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.
[0108] This other base oil typically is present in an amount
ranging from about 0.1 to about 70 weight percent, or from about 1
to about 60 weight percent, or from about 1 to about 50 weight
percent, or from about 1 to about 40 weight percent, or from about
1 to about 30 weight percent, or from about 1 to about 20 weight
percent, or from about 1 to about 10 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 ignition and compression-ignited
engines. The base oil conveniently has a kinematic viscosity,
according to ASTM standards, of about 2.5 cSt to about 12 cSt (or
mm.sup.2/s) at 100.degree. C. and preferably of about 2.5 cSt to
about 9 cSt (or mm.sup.2/s) at 100.degree. C. Mixtures of synthetic
and natural base oils may be used if desired. Mixtures of Group
III, IV, and V may be preferable.
Other Additives
[0109] 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 dispersants, corrosion inhibitors, rust inhibitors,
metal deactivators, extreme pressure additives, anti-seizure
agents, wax modifiers, viscosity index improvers, viscosity
modifiers, fluid-loss additives, seal compatibility agents,
friction modifiers, lubricity agents, anti-staining agents,
chromophoric agents, defoamants, demulsifiers, emulsifiers,
densifiers, wetting agents, gelling agents, tackiness agents,
colorants, and others. For a review of many commonly used
additives, see Klamann in Lubricants and Related Products, Verlag
Chemie, Deerfield Beach, Fla.; ISBN 0-89573-177-0. Reference is
also made to "Lubricant Additives" by M. W. Ranney, published by
Noyes Data Corporation of Parkridge, N J (1973); see also U.S. Pat.
No. 7,704,930, the disclosure of which is incorporated herein in
its entirety. These additives are commonly delivered with varying
amounts of diluent oil, that may range from 5 weight percent to 50
weight percent.
[0110] 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.
[0111] 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.
[0112] 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 2 Typical Amounts of Other Lubricating Oil
Components Approximate Approximate Compound wt % (Useful) wt %
(Preferred) Antiwear 0.1-2 0.5-1 Dispersant 0.1-20 0.1-8 Detergent
0.1-20 0.1-8 Antioxidant 0.1-5 0.1-1.5 Friction Modifier 0.01-5
0.01-1.5 Pour Point Depressant 0.0-5 0.01-1.5 (PPD) Anti-foam Agent
0.001-3 0.001-0.15 Viscosity Index Improver 0.0-8 0.1-6 (pure
polymer basis) Inhibitor and Antirust 0.01-5 0.01-1.5
[0113] 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.
[0114] The following non-limiting examples are provided to
illustrate the disclosure.
EXAMPLES
[0115] Formulations and the oxidation test results are set forth in
FIGS. 1 and 2. All of the ingredients used herein are commercially
available.
[0116] In the testing, a bench oxidation test (Sequence IIIE
screener) was conducted at 165.degree. C., under a flow of 500
ml/min of air, with 40 ppm of iron from added ferric
acetylacetonate as catalyst. Oil samples were taken periodically
and their viscosities at 40.degree. C. were measured with a
Houillon viscometer. The time (hours) to reach 200% viscosity
increase was recorded for each oil. The Sequence IIIG test was
conducted in accordance with ASTM D7320.
[0117] In the High Pressure Differential Scanning calorimetry
(HPDSC) test, the oxidation onset temperature is measured with a
Universal V4.5A TA instrument equipped with a Q20 Tzero Pressure
DSC Cell. The test method is similar to ASTM E2009-08 Test Method B
except that 500 psig of air is used instead of 500 psig of oxygen
and the sample size is 3.0+/-0.2 mg. The pressurized sample is
first equilibrated at 50 C and then ramped up to 400 C at 10
C/min.
[0118] In FIG. 1, comparative Example 1 is a typical synthetic
engine oil with conventional synthetic base oil, viscosity index
improver, dispersant, detergent, antioxidant, pour point
depressant, antifoam additive, etc. Its Sequence IIIE screener
bench oxidation test result was 322 hours and its Seq. IIIG engine
test was 54.3% increase in viscosity. Comparative Example 2 is a
PAO based engine oil formulation and its components are shown in
FIG. 1. It contains a mixture of primary and secondary zinc
dialkyldithiophosphate, a molybdenum dialkyldithiophosphate, a
calcium salicylate detergent, and other additives. Its Sequence
IIIE screener bench oxidation test result was 182 hours.
Comparative Example 3 contains a monoester iso-octadecyl
iso-octadecanoate (2-(4,4-dimethylpentan-2-yl)-5,7,7-trimethyloctyl
2-(4,4-dimethylpentan-2-yl)-5,7,7-trimethyloctanoate) base oil, a
secondary zinc dialkyldithiophosphate, a non-ionic detergent, and
other additives. Its Sequence IIIE screener bench oxidation result
was 236 hours. Example 1 contains the same base oil and additives
except the 1.0 wt % secondary zinc dialkyldithiophosphate was
replaced by 0.25 wt % of an amine phosphate and 0.1 wt % of a
dithiophosphate. Unexpectedly, the Sequence IIIE screener bench
oxidation test result improved significantly to 993 hours.
[0119] Further, in FIG. 1, Comparative Example 4 contains a
pentaerythritol ester of highly branched acids (Nycoperf 1040X), a
phenolic antioxidant, a p, p'-dioctyldiphenylamine antioxidant, a
secondary zinc dialkyldithiophosphate, and a molybdenum
dialkyldithiophosphate. Its Sequence IIIE screener bench oxidation
test result was 128 hours. In Example 2, the p,
p'-dioctyldiphenylamine antioxidant in Comparative Example 4 was
replaced by an polymerized aminic antioxidant concentrate and the
secondary zinc dialkyldithiophosphate and molybdenum
dialkyldithiophosphate in Comparative Example 4 were replaced by an
amine phosphate and Hitec 3333, a dithiophosphate, the Sequence
IIIE screener result was improved significantly to over 1100 hours.
The Sequence IIIG engine test also showed only 26.1% increase in
viscosity.
[0120] In FIG. 2, Example 3 contains polymerized aminic antioxidant
concentrate, amine phosphate, dithiophosphate, and is based on bis
(3,5,5-trimethylhexyl) adipate ester. Its Sequence IIIE screener
result was 393 hours. In Example 4, TMP ester of
3,5,5-trimethylhexanoic acid and isobutanoic acid (50/50) was used.
Its Sequence IIIE screener result was 421 hours. Examples 5 and 6
were based on TMP ester of 3,5,5-trimethylhexanoic acid and
neopentanoic acid (50/50). The only differences were that Example 5
used an octylated/butylated diphenylamine antioxidant and a
viscosity index improver while Example 6 used a polymerized aminic
antioxidant concentrate and no viscosity index improver. The
Sequence IIIE screener results for Examples 5 and 6 were 513 and
734 hours, respectively, indicating the benefit of polymerized
aminic antioxidant concentrate. Examples 7 and 8 were based on TMP
ester of 3,5,5-trimethylhexanoic acid. The only differences were
that Example 7 used an octylated/butylated diphenylamine
antioxidant and a viscosity index improver while Example 8 used a
polymerized aminic antioxidant concentrate and no viscosity index
improver. The Sequence IIIE screener results for Examples 7 and 8
were both higher than 1100, respectively.
[0121] By comparing Examples 7 and 8 with Examples 5 and 6, it is
clear that the longer alkyl chain length is beneficial in oxidation
stability in these ashless formulations. Example 9 is based on a
mixture of bis (3,5,5-trimethylhexyl) adipate and TMP ester of
3,5,5-trimethylhexanoic acid. Its Sequence IIIE screener result was
782 hours. Examples 10-12 are the same as Example 8 but with
different combination of ashless antiwear additives. Example 10
contains 0.25 wt % of amine phosphate and 0.2 wt % of Additin RC
2411, a sulfurized triglyceride. Example 11 contains 0.2 wt % of
Additin RC 2411, a sulfurized triglyceride and 0.28 wt % of Additin
RC3890, and a dithiophosphate. Example 12 contains 0.2 wt % of
Additin RC 2411, sulfurized triglyceride and 0.51 wt % of Additin
RC 3770, an amine salt of acid phosphate based on C8 alcohol. The
Sequence IIIE screener results of Examples 10-12 are all higher
than 1100 hours. It is also surprising to observe that the HPDSC
results of Example 12 are the best.
[0122] In FIG. 3, Examples 13-16 showed additional combinations of
Additin RC 2411, a sulfurized triglyceride, and Additin RC 3770, an
amine salt of acid phosphate based on C8 alcohol and the Sequence
IIIE screener and HPDSC results.
PCT and EP Clauses:
[0123] 1. A method for improving oxidative stability of a
lubricating oil in an engine or other mechanical component
lubricated with the lubricating oil by using as the lubricating oil
an ashless formulated oil, said ashless formulated oil having a
composition comprising a lubricating oil base stock as a major
component; and a mixture of (i) at least one ashless antiwear
additive, (ii) at least one ashless detergent, and (iii) at least
one aminic antioxidant, as minor components; wherein the
lubricating oil base stock comprises at least one branched polyol
ester, which is obtained by reacting one or more polyhydric
alcohols with one or more branched mono-carboxylic acids containing
at least 4 carbon atoms, and wherein the lubricating oil base stock
is present in an amount from 30 to 99.8 mass percent, based on the
total mass of the lubricating oil.
[0124] 2. The method of clause 1 wherein oxidative stability is
improved, as compared to oxidative stability achieved using a
lubricating oil other than the ashless formulated oil.
[0125] 3. The method of clauses 1 and 2 wherein the one or more
polyhydric alcohols are selected from the group consisting of
trimethylol propane, pentaerythritol, neopentyl glycol, trimethylol
ethane, 2-methyl-2-propyl-1,3-propanediol, and
dipentaerythritol.
[0126] 4. The method of clauses 1-3 wherein the one or more
branched mono-carboxylic acids containing at least 4 carbon atoms
are selected from the group consisting of 3,5,5-trimethyl hexanoic
acid (TMH), 2,2-dimethyl propionic acid (neopentanoic acid),
neoheptanoic acid, neooctanoic acid, neononanoic acid, iso-hexanoic
acid, neodecanoic acid, 2-ethyl hexanoic acid (2EH), isoheptanoic
acid, isooctanoic acid, isononanoic acid, and isodecanoic acid.
[0127] 5. The method of clauses 1-4 wherein the at least one
branched polyol ester is selected from the group consisting of
trimethylol propane ester of 3,5,5-trimethyl hexanoic acid (TMH),
trimethylol propane ester of 2,2-dimethyl propionic acid
(neopentanoic acid), trimethylol propane ester of neoheptanoic
acid, trimethylol propane ester of neooctanoic acid, trimethylol
propane ester of neononanoic acid, trimethylol propane ester of
iso-hexanoic acid, trimethylol propane ester of neodecanoic acid,
trimethylol propane ester of 2-ethyl hexanoic acid (2EH),
trimethylol propane ester of isoheptanoic acid, trimethylol propane
ester of isooctanoic acid, trimethylol propane ester of isononanoic
acid, and trimethylol propane ester of isodecanoic acid.
[0128] 6. The method of clauses 1-5 wherein the at least one
branched polyol ester is selected from the group consisting of
pentaerythritol ester of 3,5,5-trimethyl hexanoic acid (TMH),
pentaerythritol ester of 2,2-dimethyl propionic acid (neopentanoic
acid), pentaerythritol ester of neoheptanoic acid, pentaerythritol
ester of neooctanoic acid, pentaerythritol ester of neononanoic
acid, pentaerythritol ester of iso-hexanoic acid, pentaerythritol
ester of neodecanoic acid, pentaerythritol ester of 2-ethyl
hexanoic acid (2EH), pentaerythritol ester of isoheptanoic acid,
pentaerythritol ester of isooctanoic acid, pentaerythritol ester of
isononanoic acid, and pentaerythritol ester of isodecanoic
acid.
[0129] 7. The method of clauses 1-6 wherein the at least one
ashless antiwear additive is selected from the group consisting of
an amine phosphate, a thiophosphate, a dithiophosphate, an amine
salt of sulfurized phosphate, an alkylated triphenyl
phosphorothionate, a sulfurized triglyceride, and mixtures
thereof.
[0130] 8. The method of clauses 1-7 wherein the at least one
ashless detergent is selected from the group consisting of a
polyoxyethylene alkyl ether, a polyoxypropylene alkyl ether, and a
polyoxybutylene alkyl ether.
[0131] 9. The method of clauses 1-8 wherein the at least one aminic
antioxidant is selected from the group consisting of
p,p'-dioctyldiphenylamine, octylated phenyl-alpha-naphthylamine,
octylated/butylated diphenylamine, and a polymeric aminic
antioxidant.
[0132] 10. The method of clauses 1-9 wherein the at least one
ashless antiwear additive is present in an amount from 0.01 to 1.2
mass percent, based on the total mass of the lubricating oil, the
at least one ashless detergent is present in an amount from 0.01 to
6 mass percent, based on the total mass of the lubricating oil, and
the at least one aminic antioxidant is present in an amount from
0.01 to 5 mass percent, based on the total mass of the lubricating
oil.
[0133] 11. The method of clauses 1-10 wherein the ashless
formulated oil further comprises one or more of a viscosity
modifier, dispersant, pour point depressant, corrosion inhibitor,
metal deactivator, seal compatibility additive, anti-foam agent,
inhibitor, and anti-rust additive.
[0134] 12. The method of clauses 1-11 wherein the engine or other
mechanical component comprises a high energy density gasoline
engine equipped with turbo chargers, or gasoline particular filters
(GPFs).
[0135] 13. The method of clauses 1-12 wherein the lubricating oil
is a passenger vehicle engine oil (PVEO).
[0136] 14. An ashless lubricating oil having a composition
comprising a lubricating oil base stock as a major component; and a
mixture of (i) at least one ashless antiwear additive, (ii) at
least one ashless detergent, and (iii) at least one aminic
antioxidant, as minor components; wherein the lubricating oil base
stock comprises at least one branched polyol ester, which is
obtained by reacting one or more polyhydric alcohols with one or
more branched mono-carboxylic acids containing at least 4 carbon
atoms; and wherein the lubricating oil base stock is present in an
amount from 30 to 99.8 mass percent, based on the total mass of the
ashless lubricating oil.
[0137] 15. A method for improving high temperature stability of a
lubricating oil in an engine or other mechanical component
lubricated with the lubricating oil by using as the lubricating oil
an ashless formulated oil, said ashless formulated oil having a
composition comprising a lubricating oil base stock as a major
component; and a mixture of (i) at least one ashless antiwear
additive, (ii) at least one ashless detergent, and (iii) at least
one aminic antioxidant, as minor components; wherein the
lubricating oil base stock comprises at least one branched polyol
ester, which is obtained by reacting one or more polyhydric
alcohols with one or more branched mono-carboxylic acids containing
at least 4 carbon atoms, and at least one alkylated naphthalene;
and wherein the lubricating oil base stock is present in an amount
from 30 to 99.8 mass percent, based on the total mass of the
lubricating oil.
[0138] 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.
[0139] 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.
[0140] 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