Lubricant and additive formulation

Abstract

A lubricant composition for use as a concentrate and motor oil having an enhanced thermal conductivity. One preferred composition contains a lubricant composition, nanomaterial, and a dispersing agent or surfactant for the purpose of stabilizing the nanomaterial. One preferred nanomaterial is a high thermal conductivity graphite, exceeding 80 W / m in thermal conductivity. Carbon nano material or nanostructures such as nanotubes, nanofibrils, and nanoparticles formed by grounding and / or milling graphite to obtain a mean particle size less than 500 nm in diameter, and preferably less than 100 nm, and most preferably less than 50 nm. Other high thermal conductivity carbon materials are also acceptable. To confer long-term stability, the use of one or more chemical dispersants or surfactants is useful. The graphite nanomaterials contribute to the overall fluid viscosity and providing a very high viscosity index. Particle size and dispersing chemistry is controlled to get the desired combination of viscosity and thermal conductivity increase from the lubricant. The resulting fluids have unique properties due to the high thermal conductivity and high viscosity index of the suspended particles, as well as their small size.

Description

BACKGROUND OF THE INVENTION [0001] This application is a Continuation-In-Part of copending U.S. application Ser. No. 10 / 206,852 filed on Jul. 26, 2002 which claims priority from Ser. No. 09 / 520,738 filed on Mar. 7, 2000; which claims priority from U.S. Pat. No. 6,034,038 which issued on Mar. 7, 2000; which claims priority from U.S. Pat. No. 5,962,377 issued on Oct. 5, 1999; which claims priority from U.S. Pat. No. 5,763,369 which issued on Jun. 9, 1998 and U.S. Pat. No. 5,641,731 which issued on Jun. 24, 1997; and U.S. application Ser. No. 10 / 737,731 filed on Dec. 16, 2003; Ser. No. 10 / 730,762 filed on Dec. 8, 2003 which claims priority from PCT / US02 / 16888 filed on May 30, 2002 and from 10 / 021,767 filed on Dec. 12, 2001 which claims priority from U.S. Provisional Application Ser. No. 60 / 254,959 filed on Dec. 12, 2000 all of which are incorporated by reference herein.TECHNICAL FIELD [0002] The invention relates to the general field of additives to improve the performance of lubricati...

AI Technical Summary

Benefits of technology

[0012] The present invention comprises various formulations of lubricant additive concentrates for addition to conventional engine oil or as motor oil lubricants incorporating said additives therein as complete formulas for improving the lubricating properties of the engine oil, enhance the performance of the engine, and reduce engine wear and possibly reduce the consumption of the oil.

Problems solved by technology

Certain of these materials, however, must be used judiciously in certain applications due to their property of accelerating corrosion of metal parts, such as bearings.

Often designers will desire a fluid with higher thermal conductivity than the conventional oil, but are restricted to oil due to the many other parameters the fluid must meet.

While there have been various patents filed on lubricants containing graphite, e.g. U.S. Pat. No. 6,169,059, there are none which specifically rely on graphite to improve the thermal conductivity of the fluid formulated for specific applications.

Furthermore, there are none which teach specifically the use of nanometer-sized graphite with mean particle size much significantly less than 1000 nm in order to increase thermal conductivity and that reducing particle size improves thermal conductivity.

While graphite-containing automotive engine oil was once commercialized (Arco graphite), the potential to use graphite as a heat transfer improving material in this oil was not realized.

On the other hand, the use of graphite in lubricants for recirculating systems was made unpopular, partly due to evidence that micron size graphite could “pile up” in restricted flow areas in concentrated contacts, thereby leading to lubricant starvation.

Previously, naturally formed “nano-graphites” have not been available in the marketplace at all.

Additionally, the heat transfer requirements are significant.

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