IMPROVED HIGH TEMPERATURE LUBRICANT COMPOSITIONS

Description

BACKGROUND OF THE INVENTION

[0001] 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°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.

[0002] 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.

[0003] 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.

[0004] 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.

[0005] A few types of compounds are mutinely 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.

[0006] 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.

[0007] 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 oxidationdue 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. Patent No. 6,465,400 discloses a lubricant composition prepared by mixing aromatic esters with an additional base oil and antioxidants.

[0008] 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 β 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. Patent 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: Patent No. 6,436,981 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. Patent 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 US4477383 discloses neopenthyl polyol ester of isostearic acid as Lubricant base stock.

[0009] 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.

[0010] 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.

[0011] 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

[0012] The present invention includes a lubricant composition that has at least one polyol polyester. The polyol polyester is the reaction product of at least one neopentyl polyol and 5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic acid which reaction product is present in the lubricant composition in an amount of from 0.5 to 99.5% by weight of the lubricant composition based on the total weight of the lubricant composition.

[0013] 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.

[0014] 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. The reaction product is a base oil in the composition, and the composition also has at least one additional base oil.

[0015] 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 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.

[0016] 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 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.

[0017] 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 wherein the reaction product is a base oil in the composition.

[0018] The method may further comprise providing at least one additional base oil. The base oil can be present in an amount of from 5 to about 50 percent by weight of the lubricant composition and the additional base oil is present from about 50 to 90 percent of the lubricant composition. Preferably the method may further comprise providing from about 0.5 to about 15 percent by weight based on a weight of the lubricant composition of at least one lubricant protective additive. Also preferable the method may further comprise providing from about 0.1 to about 10 percent by weight based on a weight of the lubricant composition of at least one metal protective additive.

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-uitnethyl-2-(1,3,3-trimethylbutyl)-octanoic acid" herein included within the scope thereof arc 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 In addition, it jncludes 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-tritnethylbutyl)-octanoic acid, 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 used in amounts of about 0.5 to about 99.5 percent by we ight 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 for example also in amounts of from 50 to 90 percent of the lubricant composition, and may be preferably a poly α - olefin, 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 hydropcroxide theory in its most basic form can be summarized in the series of reaction steps depicted below:

Step	Reaction
formation of free radical	RH → R• + •H
formation of peroxy radical	R• + O2 → ROO•
formation of hydroperoxide	ROO• + RH → ROOH + R•
Propagation	ROOH → RO• + •OH
	RO• + RH → ROH + R•
	HO• + RH → HOH + R•

[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^™ Isostearic Acid, from Nissan America Chemical Corporation, Houston, Texas, USA) is depicted below:

[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)-actanoic acid. 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°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, trimelhylolpropane, 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 monopentaerythrical 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 neopentylpolyol and 5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic acid (and its variations as noted above) 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 α-olefins, polymer esters, such as, for example, Ketjenlube®, 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 polymer 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, monahexyl 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 diphenylanzine; hindered alkylphenols; benzenepropanoic acid, 3,5-bis(1,1-dimethylathyl)-4-hydroxy-, thiodi-2,7-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]methyl]-1,3-propanediyl ester;

[0034] thiophenolic 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, Pennsylvania, 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® 81, commercially available from RT Vanderbilt Corporation, Norwalk, Connecticut, USA) and N-phenyl-1,1,3,3-tetramethylbutylnaphthalen-1-amine (Irganox® LO-6, commercially available for Ciba Specialty Chemicals Corporation, Tarrytown, New York, 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°C was held for 5 ½ 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 1

Component	Parts Per 100 Parts	Moles Per 100 Parts
Trimethylolpropane	13.6	0.101
5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic acid	86.4	0.304

[0038] About 0.10 parts per 100 parts tetrabutyltitanate was added to the reaction mixture, and the mixture was heated to from about 180°C to about 250°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 2

Property, Units	Teat 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°C, cSt	ASTM D-445	2,411
Kinematic Viscosity @ 100°C, cSt	ASTM D-445	44.6
Viscosity Index	ASTM D-2270	-22
Flash Point (C.O.C), °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-trimcthyl-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 3

Component	Parts Per 100 Parts	Moles Per 100 Parts
Trimethylolpropane	9.5	0.071
Pentaerythritol	3.2	0.024
5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic acid	87.3	0.307

[0040] About 0.10 parts per 100 parts tetrabutyltitanate was added to the reaction mixture, and the mixture was heated to from about 180°C to about 250°C. The pressure was slowly reduced until sufficient conversion was obtained. The crude ester was further purified by stream distillation and filtration. The result was a yellow viscous liquid possessing the following properties listed in Table 4:

TABLE 4

Property, Units	Test Method	Result
Total Acid Number, mg KOH/g	ASTM D-972	0.31
Hydroxy Number, mg KOH/g	ASTM D-1957	0.42
Kinematic Viscosity @ 40°C, cSt	ASTM D-445	3,157
Kinematic Viscosity @ 100°C, cSt	ASTM D-445	53.8
Viscosity Index	ASTM D-2270	-8
Flash Point (C.O.C), °C	ASTM D-92	286
Evaporation Loss, %		44.1
Deposit 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 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 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°C, cSt	ASTM D-445	401.4
Kinematic Viscosity @100°C, cSt	ASTM D-445	20.0
Viscosity Index	ASTM D-2270	35
Flash Point (C.O.C), °C	ASTM D-92	270
. Pour Point, °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 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 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°C, cSt	ASTM D-445	363.0
Kinematic Viscosity @ 100°C, cSt	ASTM D-445	20.8
Viscosity Index	ASTM D-2270	58
Flash Point (C.O.C), °C	ASTM D-92	290
Pour point, °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 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 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°C, cSt	ASTM D-445	489
Kinematic Viscosity @ 100°C, cSt	ASTM D-445	27.0
Viscosity Index	ASTM D-2270	27
Flash Point (C.O.C), °C	ASTM D-92	306
Pour Point, °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°C with mechanical agitation until a clear uniform solution was obtained.

TABLE 11

Component	Mixture A Parts Per 100 Parts	Mixture B Parts Per 100 Parts
TMPTTBO	29.1	---
Poly α-olefin 40	67.9	58.2
Poly α-olefin 100	---	38.8
Vanlube® 81	1.5	1.5
Irganox® 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 5 ½ hours at 288°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 bolow in Table 12:

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.

Claims

1. A lubricant composition comprising at least one polyol polyester, which polyol polyester is the reaction product of:

a) at least one neopentyl polyol, and

b) 5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)-octanoic acid

which reaction product is present in the lubricant composition in an amount of from 0.5 to 99.5 % by weight of the lubricant composition, based on the total weight of the lubricant composition.

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 1 to 95 percent by weight of the lubricant composition and the additional base oil is 1 to 95 percent of the lubricant composition.

5. 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.

6. The lubricant composition of claim 1, further comprising from 0.5 to 15 percent by weight based on a weight of the lubricant composition of at least one lubricant protecting additive.

7. The lubricant composition of claim 6, wherein the lubricant protecting additive is present in the amount of up to 5 percent by weight based on the weight of the lubricant composition.

8. The lubricant composition of claim 6, 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-amino; 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-oxapropoxy]methyl]-1,3-propanediyl ester; thiiophenolic derivatives; and mixtures; derivatives; and combinations thereof.

9. The lubricant composition of claim 1, further comprising from 0.1 to 10 percent by weight of at least one metal protecting additive based on a weight of the lubricant composition.

10. The lubricant composition of claim 9, wherein the metel protecting additive is present in the amount of up to 5 percent by weight based on the weight of the lubricant composition.

11. The lubricant composition of claim 9, wherein the metal protecting additive is selected from the group consisting of t-butylphenyl phosphates, amines; branched atkyls of from 11 to 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.

12. 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 wherein the reaction product is a base oil in the composition,

b) from 0.5 to 15 percent by weight of at least one lubricant protecting additive, and

c) from 0.1 to 10 percent by weight of at least one metal protecting additive.

13. The method of lubricating, according to claim 12, wherein the lubricant composition further comprises at least one additional base oil.

14. The method of lubricating, according to claim 13, wherein the lubricant composition comprises 5 to 50 percent of the reaction product (a) and 50 to 90 percent of the at least one additional base oil.

15. 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 wherein the reaction product is a base oil in the composition.

Ansprüche

1. Schmiermittelzusammensetzung, die mindestens ein Polyesterpolyol umfasst, wobei das Polyesterpolyol das Reaktionsprodukt von Folgendem ist:

a) mindestens einem Neopentylpolyol und

b) 5,7,7-Trimethyl-2-(1,3,3-trimethylbutyl)-Octansäure

wobei das Reaktionsprodukt in der Schmiermittelzusammensetzung in einer Menge von 0,5 bis 99,5 Gew.-% der Schmiermittelzusammensetzung auf der Grundlage des Gesamtgewichts der Schmiermittelzusammensetzung vorhanden ist.

2. Schmiermittelzusammensetzung nach Anspruch 1, wobei das Neopentylpolyol aus der Gruppe ausgewählt ist, die aus Neopentylglycol, Trimethylolpropan, Trimethylolethan, Monopentaerythrit, Ditrimethylolpropan, Dipentaerythrit, Tripentaerythrit und Tetrapentaerythrit besteht.

3. Schmiermittelzusammensetzung nach Anspruch 1, wobei das Reaktionsprodukt ein Grundöl in der Zusammensetzung ist und die Zusammensetzung überdies mindestens ein zusätzliches Grundöl umfasst.

4. Schmiermittelzusammensetzung nach Anspruch 3, wobei das Grundöl von 1 bis 95 Gewichtsprozent der Schmiermittelzusammensetzung ausmacht und das zusätzliche Grundöl von 1 bis 95 Prozent der Schmiermittelzusammensetzung ausmacht.

5. Schmiermittelzusammensetzung nach Anspruch 4, wobei das zusätzliche Grundöl ein synthetischer Ester ist, der aus der Gruppe ausgewählt ist, die aus Neopentylpolyolestern, komplexen Polyesterpolyolen, alkylierten Naphtalinen und aromatischen Estern besteht.

6. Schmiermittelzusammensetzung nach Anspruch 1, die überdies zwischen 0,5 und 15 Gewichtsprozent von mindestens einem Schmiermittel-Schutzadditiv auf der Grundlage eines Gewichts der Schmiermittelzusammensetzung umfasst.

7. Schmiermittelzusammensetzung nach Anspruch 6, wobei das Schmiermittel-Schutzadditiv in einer Menge von bis zu 5 Gewichtsprozent auf der Grundlage des Gewichts der Schmiermittelzusammensetzung vorhanden ist.

8. Schmiermittelzusammensetzung nach Anspruch 6, wobei das Schmiermittel-Schutzadditiv aus der Gruppe ausgewählt ist, die aus Benzolamin, N-Phenyl-Reaktionsprodukten mit 2,4,4-Trimethylpenten; N-Phenyl-1,1,3,3-tetramethylbutylnaphthalen-1-amin; Butylhydroxytoluol; alkyliertem Diphenylamin; nonylicrtcm Diphenylamin, styrolisiertem Diphenylamin; gehinderten Alkyphenolen, Benzolpropansäure; 3,5-Bis(1,1-dimethylethyl)-4-hydroxy-, Thiodi-2,1-ethandiylester; Benzolpropansäure, 3,5-Bis(1,1-dimethylethyl)-4-hydroxy-, 2,2-Bis[[3-[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]-1-oxopropoxy]methyl]-1,3-propandiylester; Thiophenolderivaten; und Gemischen; Derivaten; und Kombinationen davon besteht.

9. Schmiermittelzusammensetzung nach Anspruch 1, die überdies von 0,1 bis 10 Gewichtsprozent von mindestens einem Metallschutzadditiv auf der Basis eines Gewichts der Schmiermittelzusammensetzung umfasst.

10. Schmiermittelzusammensetzung nach Anspruch 9, wobei das Metallschutzadditiv in der Menge von bis zu 5 Gewichtsprozent auf der Grundlage des Gewichts der Schmiermittelzusammensetzung vorhanden ist.

11. Schmiermittelzusammensetzung nach Anspruch 9, wobei das Metallschutzadditiv aus der Gruppe ausgewählt ist, die aus t-Butylphenylphosphaten, Aminen; verzweigten Alkyln aus 11 bis 14 Kohlenstoffatomen, Monoheyxl- und Dihexylphosphaten, Isopropylphenylphosphaten; Trikresylphosphaten; Trixylylphosphaten; Di(noctyl)phosphat; alkyliertem Triphenylphosphorthionat, Triphenylthiophosphat; Benzotriazol; Tolyltriazol; und Gemischen; Derivaten; und Kombinationen davon besteht.

12. Verfahren zum Schmieren einer Metallfläche, umfassend
das Aufbringen einer Schmiermittelzusammensetzung auf eine Metallfläche, wobei die Schmiermittelzusammensetzung Folgendes umfasst:

a) ein Reaktionsprodukt von mindestens einem Neopentylpolyol und 5,7,7-Trimethyl-2-(1,3,3-trimethylbutyl)-Octansäure, wobei das Reaktionsprodukt ein Grundöl in der Zusammensetzung ist,

b) von 0,5 bis 15 Gewichtsprozent von mindestens einem Schmiermittel-Schutzadditiv, und

c) von 0,1 bis 10 Gewichtsprozent von mindestens einem Metallschutzadditiv.

13. Schmierverfahren nach Anspruch 12, wobei die Schmiermittelzusammensetzung überdies mindestens ein zusätzliches Grundöl umfasst.

14. Schmierverfahren nach Anspruch 13, wobei die Schmiermittelzusammensetzung 5 bis 50 Prozent des Reaktionsprodukts (a) und 50 bis 90 Prozent des mindestens einen zusätzlichen Grundöls umfasst.

15. Verfahren zur Herstellung einer Schmiermittelzusammensetzung, umfassend die Reaktion von

a) mindestens einem Neopentylpolyol und

b) 5,7,7-Trimethyl-2-(1,3,3-trimethylbutyl)-Octansäure, wobei das Reaktionsprodukt ein Grundöl in der Zusammensetzung ist.

Revendications

1. Composition lubrifiante, comprenant au moins un polyester de polyol, lequel polyester de polyol est le produit de réaction:

a) d'au moins un néopentyle polyol, et

b) de 5,7,7-triméthyl-2-(1,3,3-triméthylbutyl)-acide octanoïque,

lequel produit de réaction est présent dans la composition lubrifiante à raison d'une quantité de 0,5 à 99,5 % en poids de la composition lubrifiante, sur la base du poids total de la composition lubrifiante.

2. Composition lubrifiante selon la revendication 1, dans laquelle le néopentyle polyol est sélectionné dans le groupe composé de néopentyle glycol, triméthylolpropane, triméthyloléthane, monopentaérythritol, ditriméthylolpropane, dipentaérythritol, tripentaérythritol, et tétrapentaérythritol.

3. Composition lubrifiante selon la revendication 1, dans laquelle le produit de réaction est une huile de base dans la composition, et la composition comprend également au moins une huile de base supplémentaire.

4. Composition lubrifiante selon la revendication 3, dans laquelle l'huile de base est de 1 à 95 pour cent en poids de la composition lubrifiante, et l'huile de base supplémentaire est de 1 à 95 pour cent de la composition lubrifiante.

5. Composition lubrifiante selon la revendication 4, dans laquelle l'huile de base supplémentaire est un ester synthétique sélectionné dans le groupe composé d'esters de néopentyle polyol, de polyesters de polyol complexes, de naphtalènes alkylés et d'esters aromatiques.

6. Composition lubrifiante selon la revendication 1, comprenant également de 0,5 à 15 pour cent en poids sur la base d'un poids de la composition lubrifiante d'au moins un additif de protection de lubrifiant.

7. Composition lubrifiante selon la revendication 6, dans laquelle l'additif de protection de lubrifiant est présent à raison d'une quantité allant jusqu'à 5 pour cent en poids sur la base du poids de la composition lubrifiante.

8. Composition lubrifiante selon la revendication 6, dans laquelle l'additif de protection de lubrifiant est sélectionné dans le groupe composé de benzénamine, produits de réaction de N-phényle avec 2,4,4-triméthylpentène ; N-phényl-1,1,3,3-tétraméthylbutylnaphtalène-1-amine ; hydroxytoluène butylé ; diphénylamine alkylée ; diphénylamine nonylée ; diphénylamine styrénée ; alkylphénols empêchés ; acide benzènepropanoïque ; 3,5-bis(1,1-diméthyléthyl)-4-hydroxy-, thiodi-2,1-éthanediyl ester ; acide benzénepropanoïque, 3,5-bis(1,1-diméthyléthyl)-4-hydroxy-, 2,2-bis[[3-[3,5-bis(1,1-diméthyléthyl)-4-hydroxyphényl]-1-oxopropoxy]méthyl]-1,3-propanediyl ester ; dérivés thiophénoliques ; et leurs mélanges ; dérivés ; et combinaisons.

9. Composition lubrifiante selon la revendication 1, comprenant étalement de 0,1 à 10 pour cent en poids d'au moins un additif de protection du métal sur la base d'un poids de la composition lubrifiante.

10. Composition lubrifiante selon la revendication 9, dans laquelle l'additif de protection du métal est présent à raison d'une quantité allant jusqu'à 5 pour cent en poids sur la base du poids de la composition lubrifiante.

11. Composition lubrifiante selon la revendication 9, dans laquelle l'additif de protection du métal est sélectionné dans le groupe composé de phosphates de t-butylphényl, amines ; alkyls ramifiés de 11 à 14 atomes de carbone, phosphates de monohexyle et de dihexyle, isopropyl-phénylphosphates ; phosphates de tricrésyle ; phosphates de trixylyle ; di(n-octyl)phosphate ; triphénylphosphorothionate alkylé ; triphénylthiophosphate ; benzotriazole ; tolyltriazole ; et leurs mélanges ; dérivés ; et combinaisons.

12. Procédé de lubrification d'une surface métallique, comprenant les étapes suivantes :

l'application d'une composition lubrifiante sur une surface métallique, la composition lubrifiante comprenant :

a) un produit de réaction d'au moins un néopentyle polyol et de 5,7,7-triméthyl-2-(1,3,3-triméthylbutyl)-acide octanoïque, dans lequel le produit de réaction est une huile de base dans la composition

b) de 0,5 à 15 pour cent en poids d'au moins un additif de protection de lubrifiant, et

c) de 0,1 à 10 pour cent en poids d'au moins un additif de protection du métal.

13. Procédé de lubrification selon la revendication 12, dans lequel la composition lubrifiante comprend également au moins une huile de base supplémentaire.

14. Procédé de lubrification selon la revendication 13, dans lequel la composition lubrifiante comprend de 5 à 50 pour cent du produit de réaction (a) et de 50 à 90 pour cent de l'huile de base supplémentaire au moins au nombre de un.

15. Procédé de réalisation d'une composition lubrifiante, comprenant la mise en réaction

a) d'au moins un néopentyle polyol et

b) de 5,7,7-triméthyl-2-(1,3,3-triméthylbutyl)-acide octanoïque, dans lequel le produit de réaction est une huile de base dans la composition.