Patent ID: 7947775

Claim:
A process for melt fabricating perfluoropolymer, comprising forming a mixture of submicrometer-size particles (A) of non-melt-flowable polytetrafluoroethylene having a melt creep viscosity of at least 1×10 6 Pa·s at 380° C. and submicrometer-size particles (B) of melt-fabricable perfluoropolymer having a melt flow rate of at least 0.1 g/10 min at 372° C. as measured in accordance with Table 2 of ASTM D-1238-94a by mixing together an aqueous dispersion of said submicrometer-size particles (A) of non-melt flowable polytetrafluoroethylene and an aqueous dispersion of said submicrometer-size particles (B) of melt-fabricable perfluoropolymer, separating the resultant mixture of said submicrometer-size particles (A) of non-melt flowable polytetrafluoroethylene and said submicrometer-size particles (B) of melt-fabricable perfluoropolymer from the resultant mixture of said aqueous dispersions, melt blending said resultant mixture of said submicrometer-size particles (A) of non-melt flowable polytetrafluoroethylene and said submicrometer-size particles (B) of melt-fabricable perfluoropolymer to form a melt blended mixture comprising dispersion of said submicrometer-size particles of non-melt flowable polytetrafluoroethylene in a continuous phase of said melt-fabricable perfluoropolymer, molding the resultant melt blended mixture into an article, and wherein said non-melt flowable polytetrafluoroethylene constitutes at about 4 to 40 wt % of the combined weight of said non-melt-flowable polytetrafluoroethylene and said melt-fabricable perfluoropolymer.