The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 31, 1991
Filed:
Jun. 21, 1990
Paul G Bekiarian, Claymont, DE (US);
Marlin D Buckmaster, Vienna, WV (US);
Richard A Morgan, Vienna, WV (US);
E. I. du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
Melt-processible copolymers of at least two halogenated comonomers from a defined class, especially perhalogenated comonomers, and particularly perfluorinated comonomers, of improved thermal stability are obtained by first contacting the copolymers with a stabilizing agent selected from bases (ammonia or amines) having a boiling point at normal pressure of at most 130.degree. C. and tertiary alcohols having up to 8 carbon atoms, to form an intermediate, drying the intermediate at about 70.degree.-150.degree. C., and fluorinating the intermediate at a temperature between 20.degree. C. and the lowest temperature at which the copolymer exhibits a solid state transistion, then removing excess fluorine and by-products and recovering the stabilized copolymer. Such stabilized copolymers are useful for a variety of technically important applications, including as cladding for optical fibers, substrates for electronic components, thermal laminates, pipes, tubes, and fittings, etc.