Process for producing fluorinated copolymer

摘要

To provide a process by which from a mixture containing a fluorinated copolymer, an unreacted monomer and a polymerization medium, the unreacted monomer and the polymerization medium can efficiently be recovered, and a lower polymer contained in the obtainable fluorinated copolymer can readily be reduced. A process for producing a fluorinated copolymer comprising (I) a step of polymerizing a fluorinated monomer having a carboxylic acid functional group or a sulfonic acid fanctional group and a fluorinated olefin in a polymerization medium to obtain a mixture containing a fluorinated copolymer, the unreacted monomer and the polymerization medium, (II) a step of continuously or intermittently transferring the mixture to an evaporation container equipped with a stirring machine and heating the mixture in the evaporation container with stirring to evaporate and recover the unreacted monomer and the polymerization medium and to obtain the fluorinated copolymer, and (III) a step of washing the fluorinated copolymer with a washing medium.

主权项

1. A process for producing a fluorinated copolymer, which comprises:
(I) polymerizing a fluorinated monomer having a carboxylic acid functional group or a sulfonic acid functional group and a fluorinated olefin in a polymerization medium to obtain a mixture containing a fluorinated copolymer, the unreacted monomer and the polymerization medium; (II) continuously or intermittently transferring mixture obtained in (I) to an evaporation container equipped with a stirring machine and heating the mixture in the evaporation container with stirring to evaporate and recover the unreacted monomer and the polymerization medium and to obtain the fluorinated copolymer; and (III) washing the fluorinated copolymer obtained in (II) with a washing medium.