Patent ID: 7347960

Claim:
A process for dispersion spinning non-melt-processible fluoropolymer fiber comprising the steps of: (a) forming a mixture of an aqueous dispersion of non-melt-processible fluoropolymer particles having an SSG of less than about 2.40, said fluoropolymer particles comprising a core of high molecular weight polytetrafluoroethylene and a shell of lower molecular weight polytetrafluoroethylene or modified polytetrafluoroethylene with an aqueous solution of a matrix polymer; (b) extruding the mixture into a coagulation bath containing a concentration of ions which coagulate the matrix polymer to form an intermediate fiber structure; and (c) sintering the intermediate fiber structure to decompose the matrix polymer and coalesce the non-melt-processible fluoropolymer particles to form said fiber.