PROCESS FOR PREPARING A FLUOROPOLYMER COMPOSITION

摘要

A process is provided for preparing a fluoropolymer composition. The process involves: i) combining an aqueous dispersion of melt flowable polytetrafluoroethylene and an aqueous dispersion of melt-fabricable tetrafluoroethylene/perfluoro(alkyl vinyl ether) copolymer to form a fluoropolymer aqueous dispersion, ii) coagulating the fluoropolymer aqueous dispersion to form a solid fluoropolymer phase and an aqueous phase, iii) separating the solid fluoropolymer phase from the aqueous phase to form coagulated fluoropolymer, and iv) heating the coagulated fluoropolymer at a temperature of from 280C to less than the highest melting point of the coagulated fluoropolymer for a period of time sufficient to increase the tensile modulus, increase the tensile strength, increase the MIT flex life, and decrease the melt flow rate of the coagulated fluoropolymer and thereby forming the fluoropolymer composition.