Thermally stable perfluoropolyethers and processes therefor and therewith

US7232932B2 · kind B2 · utility

Assignee

• E.I. DU PONT DE NEMOURS AND COMPANY · US

Inventors

• Jon Lee Howell · Bear, US
• Erik William Perez · Middletown, US
• Alfred Waterfeld · Freren, DE
• Chadron Friesen · Hope, GB
• Joseph Stuart Thrasher · Tuscaloosa, US

Key dates

• Filing date: Mar 30, 2004
• Grant date: Jun 19, 2007
• Expiry date: Dec 15, 2025

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C10N2070/00
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

A perfluoropolyether, a composition comprising the perfluoropolyether, a process for producing the perfluoropolyether, and a process for improving the thermostability of grease or lubricant are provided. The perfluoropolyether comprises perfluoroalkyl radical end groups in which the radical has at least 3 carbon atoms per radical and is substantially free of perfluoromethyl and perfluoroethyl end groups. The process for producing the perfluoropolyether can comprise (1) contacting a perfluoro acid halide, a C2-to C4-substituted ethyl epoxide, or a C3+ fluoroketone with a metal halide to produce an alkoxide; (2) contacting the alkoxide with either hexafluoropropylene oxide or tetrafluorooxetane to produce a second acid halide; (3) esterifying the second acid halide to an ester; (4) reducing the ester to its corresponding alcohol; (5) converting the alcohol with a base to a salt form; (6) contacting the salt form with a C3 or higher olefin to produce a fluoropolyether; and (7) fluorinating the fluoropolyether. The process for improving the thermostability of a grease or lubricant comprises combining the grease or lubricant with the composition.