VERFAHREN ZUR HERSTELLUNG VON FLUORHALTIGEN POLYMEREN UND FLUORHALTIGE POLYMERE

摘要

It is an object of the present invention to provide a method of producing a fluoropolymer high in terminal group stability and excellent in moldability. The present invention relates to a method of producing a fluoropolymer by which a melt-processable fluoropolymer (A) having a specific unstable terminal group or groups (P) is subjected to melt-kneading in a kneader comprising a stabilization treatment zone to thereby produce a fluoropolymer (B) resulting from conversion of said specific unstable terminal group or groups (P) to -CF 2 H,
said specific unstable terminal group or groups (P) comprising alkoxycarbonyl groups, fluoroalkoxycarbonyl groups and/or carboxyl group quaternary nitrogen compound salts,
the melt-kneading being carried out in the absence or presence of an alkali metal element or alkaline earth metal element,
the mass of said alkali metal element or alkaline earth metal element being not greater than 2 ppm of the composition under melt-kneading, and
the melt-kneading in said stabilization treatment zone being carried out in the presence of water.