A process is disclosed for dispersion spinning non-melt-processible
fluoropolymer fiber in which a mixture of an aqueous dispersion of
non-melt-processible fluoropolymer particles and an aqueous solution of a
matrix polymer is formed. The non-melt-processible fluoropolymer
particles have an SSG of less than about 2.40 and comprise a core of high
molecular weight polytetrafluoroethylene and a shell of lower molecular
weight polytetrafluoroethylene or modified polytetrafluoroethylene. The
mixture is extruded into a coagulation bath containing a concentration of
ions which coagulate the matrix polymer to form an intermediate fiber
structure. The intermediate fiber structure is sintered to decompose the
matrix polymer and coalesce the non-melt-processible fluoropolymer
particles to form the fiber. The present invention also provides for
spinning composition useful for the dispersion spinning of
non-melt-processible fluoropolymer fiber.