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:
Aug. 24, 2021
Filed:
Sep. 30, 2014
Arkema Inc., King of Prussia, PA (US);
James J. Henry, Downingtown, PA (US);
Arkema Inc., King of Prussia, PA (US);
Abstract
Fluoropolymers, specifically polyvinylidene fluoride (PVDF) polymers stabilized against color degradation due to high thermal exposure. The fluoropolymers are produced with free-radical initiators in the presence of surfactants containing acid end groups. The fluoropolymer resins are melt processed into final articles at high temperatures, above the melting point of the polymer. While the fluoropolymer is stable, residual acid surfactant causes discoloration during thermal processing. Stabilization is achieved by the addition of small amounts of ammonium or phosphonium cations to the fluoropolymer composition. It is believed the cations react with any residual acid to form a less reactive salt. These salts do not adversely affect the color of a melt processed product. The phosphonium or ammonium ions can be added to the fluoropolymer at any point from the polymerization step up to the thermal processing step. A preferred family of salts are quaternary alkyl ammonium halides.