FEP WITH INCREASED FLEXURAL FATIGUE STRENGTH AND A LOW LEVEL OF DIE DEPOSITS

Provided is a melt-processible perfluorinated polymer composition comprising (a) a melt-processible perfluoropolymer comprising (i) from 80 to 98% by weight of repeating units derived from tetrafluoroethylene, (ii) from 2 to 20% by weight of repeating units derived from hexafluoropropylene, and (iii) from 0 to 5% by weight of repeating units derived from further comonomers other than tetrafluoroethylene and hexafluoropropylene, and wherein the proportion by weight of the repeating units derived from hexafluoropropylene units is greater than that of the repeating units of said further comonomers, and (b) from 0.01 to 5% by weight, based on perfluoropolymer (a), of a high-molecular-weight perfluorinated polymer with a melting point at least 20° C. above that of the fluoropolymer (a). Also provided are processes for making and using such melt-processable compositions.