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.

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° 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 polymerizati...

AI Technical Summary

Problems solved by technology

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.

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.

One drawback of metal protecting additives, however, is that they can reduce stability of the base oils once added.

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.

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.

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.

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.

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.

Images