U.S. patent application number 11/699946 was filed with the patent office on 2007-08-02 for high temperature lubricant compositions.
This patent application is currently assigned to Inolex Investment Corporation. Invention is credited to Rocco Burgo, Tyler Housel.
Application Number | 20070179069 11/699946 |
Document ID | / |
Family ID | 38328024 |
Filed Date | 2007-08-02 |
United States Patent
Application |
20070179069 |
Kind Code |
A1 |
Burgo; Rocco ; et
al. |
August 2, 2007 |
High temperature lubricant compositions
Abstract
A lubricant composition useful for high temperature applications
is provided comprising at least one polyol polyester derived from
the reaction product of a neopentyl polyol with
5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic acid. The
lubricants have low evaporation loss, high resistance to oxidation,
and provide reduced deposits when utilized alone or in combination
with other materials.
Inventors: |
Burgo; Rocco; (Mullica Hill,
NJ) ; Housel; Tyler; (Lansdale, PA) |
Correspondence
Address: |
FLASTER/GREENBERG P.C.;8 PENN CENTER
1628 JOHN F. KENNEDY BLVD., 15TH FLOOR
PHILADELPHIA
PA
19103
US
|
Assignee: |
Inolex Investment
Corporation
Wilmington
DE
|
Family ID: |
38328024 |
Appl. No.: |
11/699946 |
Filed: |
January 30, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60763297 |
Jan 30, 2006 |
|
|
|
Current U.S.
Class: |
508/459 |
Current CPC
Class: |
C10M 2207/283 20130101;
C10M 105/38 20130101; C10M 2205/028 20130101; C10N 2030/08
20130101; C10M 111/04 20130101; C10M 2207/2835 20130101; C10N
2020/071 20200501; C10N 2030/10 20130101; C10M 2207/022 20130101;
C10M 159/12 20130101; C10N 2030/74 20200501; C10M 2205/0285
20130101; C10M 2207/126 20130101; C10M 2203/1065 20130101; C10N
2020/02 20130101; C10M 169/04 20130101; C10M 2207/126 20130101;
C10N 2020/071 20200501; C10M 2207/126 20130101; C10N 2020/071
20200501 |
Class at
Publication: |
508/459 |
International
Class: |
C10L 1/14 20060101
C10L001/14 |
Claims
1. A lubricant composition comprising at least one polyol
polyester, wherein the polyol polyester comprises a reaction
product of: a) at least one neopentyl polyol, and b)
5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic acid or a
reaction product, mixture, or copolymer thereof, or a further
reaction product, further mixture or further copolymer of the
reaction product.
2. The lubricant composition of claim 1, wherein the neopentyl
polyol is selected from the group consisting of neopentyl glycol,
trimethylolpropane, trimethylolethane, monopentaerythritol,
ditrimethylolpropane, dipentaerythritol, tripentaerythritol, and
tetrapentaerythritol.
3. The lubricant composition of claim 1, wherein the reaction
product is a base oil in the composition and the composition
further comprises at least one additional base oil.
4. The lubricant composition of claim 3, wherein the base oil is
from about 1 to about 95 percent by weight of the lubricant
composition and the additional base oil is about 1 to 95 percent of
the lubricant composition.
5. The lubricant composition of claim 3, wherein the base oil is
from about 5 to about 50 percent by weight of the lubricant
composition and the additional base oil is about 50 to 90 percent
of the lubricant composition.
6. The lubricant composition of claim 3, wherein the additional
base oil is selected from the group consisting of synthetic esters,
polyesters, complex polyol polyester polymers, poly
.alpha.-olefins, polymer esters, alkylated naphthalenes,
polyalkylene glycols, silicones, phosphate esters, alkylated
aromatics, silahydrocarbons, phosphazenes, polyphosphazenes,
dialkylcarbonates, cycloaliphatics, polybutenes, alkyldiphenyl
ethers, polyphenyl ethers, mineral oils, hydrocarbon oils,
triglyceride oils, vegetable oils, fatty acids having a primary
carbon chain length of about 5 to about 54 carbon atoms, and
copolymers, mixtures, derivatives, and combinations thereof.
7. The lubricant composition of claim 4, wherein the additional
base oil is a synthetic ester selected from the group consisting of
neopentyl polyol esters, complex polyol polyesters, alkylated
naphthalenes and aromatic esters.
8. The lubricant composition of claim 4, wherein the additional
base oil is a poly .alpha.-olefin.
9. The lubricant composition of claim 1, further comprising from
about 0.5 to about 15 percent by weight based on a weight of the
lubricant composition of at least one lubricant protecting
additive.
10. The lubricant composition of claim 7, wherein the lubricant
protecting additive is present in the amount of up to about 5
percent by weight based on the weight of the lubricant
composition.
11. The lubricant composition of claim 7, wherein the lubricant
protecting additive is selected from the group consisting of
benzenamine, N-phenyl-, reaction products with
2,4,4-trimethylpentene;
N-phenyl-1,1,3,3-tetramethylbutylnaphthalen-1-amine; butylated
hydroxytoluene; alkylated diphenylamine; nonylated diphenylamine;
styrenated diphenylamine; hindered alkylphenols; benzenepropanoic
acid; 3,5-bis(1,1-dimethylethyl)-4-hydroxy-, thiodi-2,1-ethanediyl
ester; benzenepropanoic acid,
3,5-bis(1,1-dimethylethyl)-4-hydroxy-,
2,2-bis[[3-[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]-1-oxopropoxy]meth-
yl]-1,3-propanediyl ester; thiphenolic derivatives; and mixtures;
derivatives; and combinations thereof.
12. The lubricant composition of claim 1, further comprising from
about 0.1 to about 10 percent by weight of at least one metal
protecting additive based on a weight of the lubricant
composition.
13. The lubricant composition of claim 10, wherein the metal
protecting additive is present in the amount of up to about 5
percent by weight based on the weight of the lubricant
composition.
14. The lubricant composition of claim 10, wherein the metal
protecting additive is selected from the group consisting of
t-butylphenyl phosphates, amines; branched alkyls of from about 11
to about 14 carbon atoms, monohexyl and dihexyl phosphates,
isopropylphenylphosphates; tricresyl phosphates; trixylyl
phosphates; di(n-octyl)phosphate; alkylated
triphenylphosphorothionate; triphenylthiophosphate; benzotriazole;
tolyltriazole; and mixtures; derivatives; and combinations
thereof.
15. A method of lubricating a metal surface, comprising: applying a
lubricant composition to a metal surface, wherein the lubricant
composition comprises: a) a reaction product of at least one
neopentyl polyol and
5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic acid or a
reaction product, mixture, or copolymer thereof wherein the
reaction product is a base oil in the composition, b) from about
0.5 to about 15 percent by weight of at least one lubricant
protecting additive, and c) from about 0.1 to about 10 percent by
weight of at least one metal protecting additive.
16. The method of lubricating, according to claim 15, wherein the
lubricant composition further comprises at least one additional
base oil.
17. The method of lubricating, according to claim 16, wherein the
lubricant composition comprises about 5 to about 50 percent of the
reaction product (a) and about 50 to about 90 percent of the at
least one additional base oil.
18. A method of making a lubricant composition, comprising reacting
a) at least one neopentyl polyol and b)
5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic acid or a
reaction product, mixture, or copolymer thereof, wherein the
reaction product is a base oil in the composition.
19. The method of claim 18, further comprising providing at least
one additional base oil.
20. The method of claim 19, wherein the base oil is from about 5 to
about 50 percent by weight of the lubricant composition and the
additional base oil is about 50 to 90 percent of the lubricant
composition.
21. The method of claim 14, further comprising providing from about
0.5 to about 15 percent by weight based on a weight of the
lubricant composition of at least one lubricant protecting
additive.
22. The method of claim 14, further comprising providing from about
0.1 to about 10 percent by weight based on a weight of the
lubricant composition of at least one metal protecting additive.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit under 35 U.S.C. 119(e)
of U.S. Provisional Application No. 60/763,297, filed Jan. 30,
2006.
BACKGROUND OF THE INVENTION
[0002] Lubricants that can maintain their structure under extremes
of temperature are useful and essential in many commercial,
domestic, and industrial applications. Such applications include,
but are not limited to, fiberglass production, wood laminating,
wood pressing, paint curing, textile production, and food baking.
Lubricants can also be used in aerospace applications in which
fluids are exposed to temperatures typically exceeding 200.degree.
C. Such high temperature lubrication fluids must also provide
sufficient lubrication of metal surfaces to prevent wear, reduce
friction, reduce energy consumption, and more importantly, prevent
failure of mechanical systems.
[0003] Lubricants that are used at high temperatures must also be
resistant to thermal and/or oxidative breakdown and polymerization.
Thermal and/or oxidative breakdown leads to the scission of
lubricant molecules, which in turn, leads to the formation of lower
molecular weight compounds that can be volatilized, depending upon
the operational conditions of a mechanical system. This process
normally results in an increased lubricant viscosity. Where the
lubricant is exposed to the atmosphere, and especially in thin
films, an increase in lubricant viscosity reduces the mobility of
the lubricant liquid, accelerates oxidation, and leads to the
formation of deposits. Such breakdown may also result in loss of
lubricant fluid and/or the production of excessive vapors and/or
smoke, or ineffective lubrication. This, in turn, can lead to
mechanical breakdown, higher energy consumption, reduced
cleanliness, poorer product quality, and higher occupational
exposure to volatile organic compounds. Polymerization can lead to
formation of deposits of semi-solid gums and hard varnishes that
can build up on metal surfaces and in work environments. This, in
turn, may lead to poorer lubrication, higher energy consumption,
and potential production stoppages due to the need to remove
deposits from the metal surfaces.
[0004] Liquid lubricant compositions typically have a base oil to
which other additives are provided. The additives impart specific
properties to the overall lubricant mixture. One class of such
additives is metal protecting additives. These exhibit beneficial
properties such as resistance to wear, protection from damage at
extreme pressure, and resistance to corrosion. Such additives are
also useful for protecting metal surfaces. One drawback of metal
protecting additives, however, is that they can reduce stability of
the base oils once added.
[0005] To alleviate such loss of stability, lubricant protecting
additives can be provided to the base oils. Lubricant protecting
additives are helpful for maintaining a lubricant's structure under
operational conditions. The most important lubricant protecting
additives are antioxidants. Antioxidants protect a base oil in a
lubricant composition and/or other additives therein from attack by
atmospheric oxygen, a harmful process also known as oxidation,
which produces unwanted free radicals and leads to instability.
Antioxidants help to stabilize base oils by helping to prevent
oxidation. The effectiveness of antioxidants is strongly influenced
by the level of stability of the base oil or oils in the
composition. Greater stability of the base oil helps to reduce
potentially adverse effects of oxidation.
[0006] A few types of compounds are routinely used as liquid base
oils in the field of high temperature lubricants, include
perfluoropolyalkyl ethers which are highly resistant to oxidation
due to the complete absence of extractable hydrogen atoms.
Polyphenylethers and alkyldiphenyl ethers are also inherently very
stable. However, their lubrication properties are poorer than other
classes of base oils, and they tend to be either incompatible
and/or not positively responsive to metal and/or lubricant
protecting additives. Additionally, due to the sophisticated
synthesis techniques and manufacturing processes required to
produce these materials, they are only produced in small quantities
unsuitable for large-scale industrial use.
[0007] Another class of compounds commonly used as liquid base oils
in the lubrication field is synthetic esters. Synthetic esters are
derived from the reaction of carboxylic acids and alcohols.
Carboxylic acids and alcohols can be synthesized to very high
purity, and thus, synthetic esters can be designed with very
defined structures that can be targeted to provide the specific
properties sought in a particular application. Synthetic esters are
generally both compatible with, and respond favorably to common
metal and lubricant protecting additives.
[0008] Esters of certain carboxylic acids and alcohols are known to
possess enhanced resistance to thermal and/or oxidative breakdown.
Two general classes of commonly used synthetic esters with one or
more of these properties are aromatic esters and neopolyol esters.
Aromatic esters are formed as a reaction product of aromatic
polycarboxylic acids, such as trimellitic acid and pyromellitic
acid, and linear and/or branched monofunctional alcohols. Such
alcohols typically have a carbon chain length of about 8 to about
13 carbon atoms. Although aromatic esters are prone to oxidation
due to the aromatic portion of the molecule, they can be useful due
to their relatively high molecular weight and structural purity
that contributes to a lower volatility. U.S. Pat. No. 6,465,400
discloses a lubricant composition prepared by mixing aromatic
esters with an additional base oil and antioxidants.
[0009] Neopolyol esters are formed from the reaction of neopentyl
polyols, such as neopentyl glycol, trimethylolpropane,
pentaerythritol, and dipentaerythritol with linear and/or branched
carboxylic acids that are typically about two to about ten carbon
atoms in chain length. Neopolyol esters as a class are generally
more resistant to oxidation than aromatic esters. They are
particularly useful due to their higher thermal and oxidative
stability which stems from the absence of hydrogens attached to
carbons that are .beta. to the ester linkage, which can lead to a
low energy oxidation pathway. The carboxylic acids used to form
such esters typically are linear and/or branched chain acids having
from about five to about ten carbon atoms. U.S. Pat. No. 4,826,633
discloses esters formed by reacting trimethylolpropane and
monopentaerythritol with a mixture of linear and branched
carboxylic acids having from 5 to 10 carbon atoms. U.S. Pat. No.
6,436,881 discloses a high temperature lubricant formulation formed
by reacting mainly dipentaerythritol with a mixture of linear and
branched carboxylic acids having from 5 to 12 carbon atoms, that
also includes a viscosity index improver. U.S. Pat. No. 6,884,861
discloses a high temperature lubricant composition including esters
formed from the reaction of certain polyols with mixtures of
carboxylic acids having a five to ten carbon chain length and/or
aromatic acids.
[0010] Neopentyl polyol polyesters that are formed from certain
relatively short chain linear or branched carboxylic acids of about
5 to about 10 carbons are particularly resistant to thermal and/or
oxidative breakdown and/or polymerization relative to neopentyl
polyol polyesters derived from longer chain carboxylic acids of
about 12 carbons and longer. Examples of shorter chain carboxylic
acids employed for forming neopentyl polyol polyester for use as
base oils in lubricant compositions are pentanoic acid, hexanoic
acid, heptanoic acid, octanoic acid, 2-ethylhexanoic acid, nonanoic
acid, 3,5,5-trimethylhexanoic acid (isononanoic acid) and decanoic
acid. The shorter chain carboxylic acids are preferred due to the
shielding effect provided by the ester linkage that makes the
hydrogen atoms on the carboxylic acid portion more resistant to
abstraction and resultant oxidative attack. Longer chain carboxylic
acids generally possess hydrogen atoms further away from the ester
linkage that do not benefit from increased stability provided from
the shielding effect of the ester linkage.
[0011] Although using shorter chain carboxylic acids improves
resistance to oxidation, the resulting molecular weight of the
ester is typically limited, which can lead to higher volatility.
Isononanoic acid is particularly resistant to oxidation due to the
reduced presence of secondary hydrogen atoms and the steric
crowding about the lone tertiary hydrogen atom. However, due to its
highly branched nature, the resulting esters generally have higher
volatility. Higher volatility of the base ester, and resulting
oxidative scission products can lead to oil thickening that
accelerates the formation of deposits, especially in thin
films.
[0012] Therefore, there is a need in the art for an improved ester
that combines the desirable thermal and oxidative stability
typically provided by the reaction of neopentyl polyols with
shorter chain carboxylic acids; the low volatility and/or low
volatility of oxidation scission products, which, in the past, have
been associated with the use of longer chain carboxylic acids to
form the neopentyl polyol ester; and the low volatility that arises
from the use of aromatic polycarboxylic acids to form the aromatic
ester.
BRIEF SUMMARY OF THE INVENTION
[0013] The present invention includes a lubricant composition that
has at least one polyol polyester. The polyol polyester comprises
the reaction product of at least one neopentyl polyol and
5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic acid or a
reaction product, mixture, or copolymer thereof, or a further
reaction product, further mixture, or further copolymer of the
reaction product.
[0014] In one embodiment, the reaction product is a base oil in a
lubricant composition. In a further embodiment, the lubricant
composition including the reaction product as a base oil comprises
at least one additional base oil. In yet a further embodiment, the
lubricant composition including the reaction product as a base oil
and comprising at least one additional base oil further comprises a
lubricant protecting additive and/or a metal protecting
additive.
[0015] One embodiment of the present invention includes providing a
lubricant composition that has at least one polyol polyester. The
polyol polyester is the reaction product of a neopentyl polyol and
5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic acid or reaction
products, mixtures, and copolymers. The reaction product is a base
oil in the composition, and the composition also has at least one
additional base oil.
[0016] The invention also includes a lubricant composition that has
at least one polyol polyester. The polyol polyester is the reaction
product of a neopentyl polyol and
5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic acid or reaction
products, mixtures, and copolymers thereof. The reaction product is
a base oil in the composition, and the composition further also has
at least one additional base oil, at least one metal protecting
additive, and/or at least one lubricant protecting additive.
[0017] Also included herein is a method of lubricating a metal
surface. The method comprises applying a lubricant composition to a
metal surface, wherein the lubricant composition comprises a) a
reaction product of at least one neopentyl polyol and
5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic acid or a
reaction product, mixture, or copolymer thereof wherein the
reaction product is a base oil in the composition, b) at least one
additional base oil, c) from about 0.5 to about 15 percent by
weight of at least one lubricant protecting additive, and d) from
about 0.1 to about 10 percent by weight of at least one metal
protecting additive.
[0018] Further, a method of making a lubricant composition, is
included. The method comprises reacting a) at least one neopentyl
polyol and b) 5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic
acid or a reaction product, mixture, or copolymer thereof, wherein
the reaction product is a base oil in the composition.
DETAILED DESCRIPTION OF THE INVENTION
[0019] The present invention relates generally to lubricant
compositions useful for high temperature applications comprising
polyol polyesters derived from
5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic acid and reaction
products, mixtures, and copolymers thereof. It should be understood
based on this disclosure hereinafter that when referring to
"5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic acid" herein
included within the scope thereof are reaction products, mixtures
and copolymers thereof.
[0020] The present invention provides lubricant compositions that
exhibit high resistance to thermal and/or oxidative breakdown
and/or polymerization, low volatility, and a low deposit formation
tendency. Examples of such lubricant compositions include, but are
not limited to, those that include the reaction product of at least
one neopentyl polyol and
5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic acid as well as
further reaction products, mixtures, and copolymers of that
reaction product. In addition, it includes lubrication compositions
that include an additive that is the reaction product of at least
one neopentyl polyol and
5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic acid as well as
mixtures, reaction products and copolymers of that reaction
product. Further, base oils are provided which are a mixture of the
reaction product of at least one neopentyl polyol and
5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic acid, and
reaction products, mixtures, and copolymers of that reaction
product's derivatives as noted above, and at least one additional
base oil such as other base compositions including various mixtures
of the reaction product noted above with at least one additional
base oil, at least one metal protecting additive and/or at least
one lubricant protecting additive.
[0021] When the reaction product noted above is used as a base oil
to a lubricant composition, it is preferred to be used in amounts
of about 0.5 to about 99.5 percent by weight of the composition,
more preferably about 1 to about 95 percent by weight or about 5 to
about 95 weight percent, and most preferably about 5 to about 50
weight percent, wherein the weight percentages are based on the
total weight percent of the lubricant composition. If additional
base oils are provided, they may be used in similar quantities, and
preferably, when the base oil including the reaction product is
about 5 to about 50 weight percent of the composition, the
additional base oil(s) make up about 50 to about 90 percent of the
lubricant composition. The ratio of the base oil having the
reaction product to the additional base oils is preferably from
about 99:1 to about 1:99, more preferably 25:75 to about 75:25,
still more preferably about 30:70 to about 70:30, and most
preferably about 50:50.
[0022] The mechanism of oxidation (autoxidation) is commonly
described by the "hydroperoxide theory." The hydroperoxide theory
in its most basic form can be summarized in the series of reaction
steps depicted below:
TABLE-US-00001 Step Reaction formation of free radical RH .fwdarw.
R.cndot. + .cndot.H formation of peroxy radical R.cndot. + O.sub.2
.fwdarw. ROO.cndot. formation of hydroperoxide ROO.cndot. + RH
.fwdarw. ROOH + R.cndot. Propagation ROOH .fwdarw. RO.cndot. +
.cndot.OH RO.cndot. + RH .fwdarw. ROH + R.cndot. HO.cndot. + RH
.fwdarw. HOH + R.cndot.
[0023] Depending upon the nature of the substrate chemical, the
specific course of reaction, the kinetics of the reaction, the rate
dependency upon temperature, or the presence of metal catalysts,
enzymes, or ultraviolet radiation that can impact the reaction
kinetics, a virtually infinite variety of by-products may be
observed. Based upon this theory, the primary factor in the
prediction of oxidation stability when inspecting a molecular
structure is the identification of hydrogen atoms that may be
easily abstracted to form free radicals. Since free radicals are
formed chemically by homolytic cleavage of carbon-hydrogen bonds, a
first estimate can be obtained simply by looking at bond
dissociation energies.
[0024] Alkyl substituents contribute electron density and stabilize
free radicals. Tertiary hydrogen atoms are most easily abstracted,
followed by secondary, then primary. The exact position of alkyl
groups within a carbon chain can also have the effect of either
stabilizing or de-stabilizing the molecule by steric crowding, or
by eliminating the possibility of non-oxidative degradation
reactions such as dehydration that can give rise to by-products
that are easily oxidized.
[0025] The structure of
5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic acid (available
commercially as Fine Oxocol.TM. Isostearic Acid, from Nissan
America Chemical Corporation, Houston, Tex., USA) is depicted
below:
##STR00001##
[0026] As can be seen from the structure, this carboxylic acid
possesses eighteen (18) carbon atoms, eight (8) sterically crowded
secondary hydrogen atoms, two (2) highly sterically crowded
tertiary hydrogen atoms, and one (1) tertiary hydrogen atom
adjacent to the carboxylic acid. All other hydrogens within this
molecule are primary. The hydrogen atoms located in close proximity
to the ester linkages are more difficult to extract. Neopentyl
polyols possess only primary hydrogen atoms.
[0027] One embodiment of the present invention is a lubricant
composition, including as a base oil and/or a liquid, a polyol
polyester formed as the reaction product of, preferably from the
esterification of, at least one neopentyl polyol and
5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic acid or its
reaction products, mixtures, and copolymers. The composition may
also include further reaction products, mixtures or copolymers of
the reaction product noted above. The preferred polyol polyester
has a viscosity of from about 100 centistokes to about 25,000
centistokes when measured at 40.degree. C. More particularly, the
polyol used to make the polyol polyester is a neopentyl polyol.
Such neopentyl polyols include, but are not limited to, neopentyl
glycol, trimethylolpropane, trimethylolethane, monopentaerythritol,
ditrimethylolpropane, dipentaerythritol, tripentaerythritol, and
tetrapentaerythritol. Such neopentyl polyols are commercially
available, however, it is within the scope of the invention to use
both commercially available neopentyl polyols as well as
synthesized or modified neopentyl polyols. Preferred polyols are
monopentaerythritol and trimethylolpropane or combinations thereof,
although minor quantities of dipentaerythritol, tripentaerythritol,
and tetrapentaerythritol may be utilized in combination or
admixture therewith.
[0028] In one embodiment, the invention encompasses a base oil that
includes a mixture of a liquid polyol polyester formed from the
esterification of at least one polyol and
5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic acid (and its
variations as noted above) or any reaction products, mixtures of
copolymers of such polyol polyester, and at least one additional
base oil. Preferred additional base oils include those known or to
be developed in the lubricant arts, such as, for example, synthetic
esters, polyesters, complex polyol polyester polymers, poly
.alpha.-olefins, polymer esters, such as, for example,
Ketjenlube.RTM., commercially available from Akzo Nobel, alkylated
naphthalenes, polyalkylene glycols, silicones, phosphate esters,
alkylated aromatics, silahydrocarbons, phosphazenes,
polyphosphazenes, dialkylcarbonates, cycloaliphatics, polybutenes,
alkyldiphenyl ethers, polyphenyl ethers, mineral oils, hydrocarbon
oils, triglyceride oils, vegetable oils, fatty acids having a
primary carbon chain length of about 5 to about 54 carbon atoms,
and copolymers, mixtures, derivatives, and combinations of these
materials.
[0029] Synthetic esters may include, but are not limited to,
neopentyl polyol esters, complex polyol polyesters, and aromatic
esters. Preferred synthetic esters are neopentyl polyol polyesters
and/or neopentyl polyol polyester polymers. Neopentyl polyol
polyesters referred to herein are the reaction products of
neopentyl polyols with at least one monofunctional carboxylic acid,
and having multiple ester linkages in the molecule. Such materials
are typically not polymeric in character. Neopentyl polyol
polyester polymers are the reaction products of neopentyl polyols
and at least one polyfunctional carboxylic acid and at least one
monofunctional carboxylic acid and/or a monofunctional alcohol as
an end capper. Such materials are polymeric in character and are
also known as complex esters or complex polyol esters.
[0030] Preferred neopentyl polyol polyesters include the reaction
products of neopentyl polyols with linear and/or branched
carboxylic acids of chain length of about 5 to about 12 carbon
atoms. Preferred neopentyl polyol polyester polymers include the
reaction products of at least one neopentyl polyol, at least one
polycarboxylic acid, and at least one linear and/or branched
monocarboxylic acid and/or alcohol of chain length of about 5 to
about 20 carbon atoms.
[0031] Such lubricant compositions preferably include such as, for
example, metal protecting additives t-butylphenyl phosphates,
amines; branched alkyls of from 11 to 14 carbon atoms, monohexyl
and dihexyl phosphates, isopropylphenylphosphates, tricresyl
phosphates, trixylyl phosphates, di(n-octyl)phosphite, alkylated
triphenylphosphorothionate, triphenylthiophosphate, benzotriazole,
tolyltriazole, and mixtures, derivatives, and combinations
thereof.
[0032] About 0.1 to about 10 percent by weight of the total
composition of at least one metal protecting additive is preferably
used when provided such an optional additive to a preferred
lubricant composition. More particularly, up to about 5 percent by
weight of the lubricant composition of metal protecting additive is
provided to the lubricant composition.
[0033] Lubricant protecting additives include any such additive
known or to be developed in the lubricant art, but are not limited
to, benzenamine, N-phenyl-, reaction products with
2,4,4-trimethylpentene;
N-phenyl-1,1,3,3-tetramethylbutylnaphthalen-1-amine; butylated
hydroxytoluene; alkylated diphenylamine; nonylated diphenylamine;
styrenated diphenylamine; hindered alkylphenols; benzenepropanoic
acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy-, thiodi-2,1-ethanediyl
ester; benzenepropanoic acid,
3,5-bis(1,1-dimethylethyl)-4-hydroxy-,
2,2-bis[[3-[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]-1-oxopropoxy]meth-
yl]-1,3-propanediyl ester;
[0034] thiphenolic derivatives, and mixtures, derivatives, and
combinations of these materials. About 0.5 to about 15 percent by
weight of at least one lubricant protecting additive is preferably
added to the lubricant composition. More particularly, up to about
5 percent by weight of an optional lubricant protecting additive is
provided to the lubricant composition.
[0035] The invention will now be explained with respect to the
following, non-limiting Examples. In the following Examples,
kinematic viscosity was tested using ASTM International, West
Conshohocken, Pa., USA, (standard test method ASTM-D-445-97 (1997).
Total acid number (TAN) was determined using ASTM D-972. Hydroxyl
value (OH) was determined using ASTM D-1957. Viscosity index (VI)
was determined using ASTM D-2270. Flash point was determined using
ASTM D-92, and pour point was determined using ASTM D-97.
[0036] Evaporation loss, deposit formation tendency, and residual
oil fluidity were assessed by the following procedure. The
lubricant base oil was blended with 1.5 wt. % each of benzenamine,
N-phenyl-, reaction products with 2,4,4-trimethylpentene
(Vanlube.RTM. 81, commercially available from RT Vanderbilt
Corporation, Norwalk, Conn., USA) and
N-phenyl-1,1,3,3-tetramethylbutylnaphthalen-1-amine (Irganox.RTM.
LO-6, commercially available for Ciba Specialty Chemicals
Corporation, Tarrytown, N.Y., USA). Two (2) grams of lubricant
liquid were placed in an aluminum weighing dish, and then placed in
a muffle furnace. The test condition of 288.degree. C. was held for
51/2 hours. Evaporation loss, deposit formation tendency, and flow
properties of the lubricant after this procedure were measured by
weight and by visual observation, respectively.
EXAMPLE 1
[0037] The lubricant composition trimethylolpropane
tri-5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoate (TMPTTBO)
was prepared by combining the following materials of Table 1 in a
batch reactor fitted with a mechanical stirrer, inert gas sparge,
vapor column, condenser, and distillate receiver. Pressure in the
reactor was controlled by a vacuum pump that was attached to the
reactor.
TABLE-US-00002 TABLE 1 Parts Per 100 Moles Per 100 Component Parts
Parts Trimethylolpropane 13.6 0.101
5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)- 86.4 0.304 octanoic
acid
[0038] About 0.10 parts per 100 parts tetrabutyltitanate was added
to the reaction mixture, and the mixture was heated to from about
180.degree. C. to about 250.degree. C. Pressure was slowly reduced
until sufficient conversion was obtained. The crude ester was
further purified by steam distillation and filtration. The result
was a yellow viscous liquid possessing the following properties
shown in Table 2:
TABLE-US-00003 TABLE 2 Property, Units Test Method Result Total
Acid Number, mg KOH/g ASTM D-972 0.38 Hydroxyl Number, mg KOH/g
ASTM D-1957 4.7 Kinematic Viscosity @ 40.degree. C., cSt ASTM D-445
2,411 Kinematic Viscosity @ 100.degree. C., cSt ASTM D-445 44.6
Viscosity Index ASTM D-2270 -22 Flash Point (C.O.C), .degree. C.
ASTM D-92 280 Evaporation Loss, % 48.8 Deposits After Heating,
Visual Minimal Fluidity After Heating, Visual Fluid
EXAMPLE 2
[0039] The lubricant composition Trimethylolpropane/Pentaerythritol
5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoate (TMPPETTBO) was
prepared by combining the following materials in Table 3 in a batch
reactor fitted with a mechanical stirrer, inert gas sparge, vapor
column, condenser, and distillate receiver. Pressure in the reactor
was controlled by a vacuum pump that was attached to the
reactor.
TABLE-US-00004 TABLE 3 Parts Per 100 Moles Per Component Parts 100
Parts Trimethylolpropane 9.5 0.071 Pentaerythritol 3.2 0.024
5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)- 87.3 0.307 octanoic
acid
[0040] About 0.10 parts per 100 parts tetrabutyltitanate was added
to the reaction mixture, and the mixture was heated to from about
180.degree. C. to about 250.degree. C. The pressure was slowly
reduced until sufficient conversion was obtained. The crude ester
was further purified by steam distillation and filtration. The
result was a yellow viscous liquid possessing the following
properties listed in Table 4:
TABLE-US-00005 TABLE 4 Property, Units Test Method Result Total
Acid Number, mg KOH/g ASTM D-972 0.31 Hydroxyl Number, mg KOH/g
ASTM D-1957 0.42 Kinematic Viscosity @ 40.degree. C., cSt ASTM
D-445 3,157 Kinematic Viscosity @ 100.degree. C., cSt ASTM D-445
53.8 Viscosity Index ASTM D-2270 -8 Flash Point (C.O.C), .degree.
C. ASTM D-92 286 Evaporation Loss, % 44.1 Deposits After Heating,
Visual Minimal Fluidity After Heating, Visual Fluid
EXAMPLE 3
[0041] A lubricant base oil was prepared by combining the following
ingredients of Table 5:
TABLE-US-00006 TABLE 5 Component Parts Per 100 Parts TMPTTBO 50
Synthetic Ester 50
[0042] The result was a yellow viscous liquid possessing the
following properties shown in Table 6:
TABLE-US-00007 TABLE 6 Property, Units Test Method Result Total
Acid Number, mg KOH/g ASTM D-972 0.17 Hydroxyl Number, mg KOH/g
ASTM D-1957 4.5 Kinematic Viscosity @ 40.degree. C., cSt ASTM D-445
401.4 Kinematic Viscosity @ 100.degree. C., cSt ASTM D-445 20.0
Viscosity Index ASTM D-2270 35 Flash Point (C.O.C), .degree. C.
ASTM D-92 270 Pour Point, .degree. C. ASTM D-97 -15 Evaporation
Loss, % 58.7 Deposits After Heating, Visual Minimal Fluidity After
Heating, Visual Fluid
EXAMPLE 4
[0043] A lubricant base oil was prepared by combining the following
ingredients of Table 7:
TABLE-US-00008 TABLE 7 Component Parts Per 100 Parts TMPTTBO 57
Synthetic Ester 43
[0044] The result was a yellow viscous liquid possessing the
following properties of Table 8:
TABLE-US-00009 TABLE 8 Property, Units Test Method Result Total
Acid Number, mg KOH/g ASTM D-972 0.26 Hydroxyl Number, mg KOH/g
ASTM D-1957 4.57 Kinematic Viscosity @ 40.degree. C., cSt ASTM
D-445 363.0 Kinematic Viscosity @ 100.degree. C., cSt ASTM D-445
20.8 Viscosity Index ASTM D-2270 58 Flash Point (C.O.C), .degree.
C. ASTM D-92 290 Pour Point, .degree. C. ASTM D-97 -21 Evaporation
Loss, % 40.8 Deposits After Heating, Visual Minimal Fluidity After
Heating, Visual Fluid
EXAMPLE 5
[0045] A lubricant base oil was prepared by combining the following
ingredients of Table 9:
TABLE-US-00010 TABLE 9 Component Parts Per 100 Parts TMPTTBO 15
Synthetic Ester 85
[0046] The result was a yellow viscous liquid possessing the
following properties of Table 10:
TABLE-US-00011 TABLE 10 Property, Units Test Method Result Total
Acid Number, mg KOH/g ASTM D-972 0.06 Hydroxyl Number, mg KOH/g
ASTM D-1957 1.9 Kinematic Viscosity @ 40.degree. C., cSt ASTM D-445
489 Kinematic Viscosity @ 100.degree. C., cSt ASTM D-445 27.0
Viscosity Index ASTM D-2270 27 Flash Point (C.O.C), .degree. C.
ASTM D-92 306 Pour Point, .degree. C. ASTM D-97 -18 Evaporation
Loss, % 71.5 Deposits After Heating, Visual Minimal Fluidity After
Heating, Visual Fluid
EXAMPLE 6
[0047] To illustrate the improvement that can be made by use of
TMPTTBO as an additive, the following mixtures of Table 11 were
prepared by blending the fluids at about 70 to about 90.degree. C.
with mechanical agitation until a clear uniform solution was
obtained.
TABLE-US-00012 TABLE 11 Mixture B Mixture A Parts Per 100 Component
Parts Per 100 Parts Parts TMPTTBO 29.1 -- Poly .alpha.-olefin 40
67.9 58.2 Poly .alpha.-olefin 100 -- 38.8 Vanlube .RTM. 81 1.5 1.5
Irganox .RTM. LO-6 1.5 1.5
[0048] The solutions were then tested for thin film heat stability.
Two grams of lubricant were placed in an aluminum weighing dish,
placed in a muffle furnace, and held for a test duration of 51/2
hours at 288.degree. C. Evaporation loss, deposits, and flow
properties of the lubricant after the test were measured by weight
and by visual observation, respectively.
[0049] The results are provided below in Table 12:
TABLE-US-00013 TABLE 12 Property, Units Mixture A Mixture B
Evaporation Loss, % 21.7 31.3 Deposits After Heating, Visual
Minimal Significant Fluidity After Heating, Visual Fluid Non Fluid
Tar
The test results indicated significant reduction in volatility,
reduced deposits, and improved fluidity of aged oil when
polyalphaolefin was replaced with TMPTTBO.
[0050] It will be appreciated by those skilled in the art that
changes could be made to the embodiments described above without
departing from the broad inventive concept thereof. It is
understood, therefore, that this invention is not limited to the
particular embodiments disclosed, but it is intended to cover
modifications within the spirit and scope of the present invention
as defined by the appended claims.
* * * * *