METHOD OF PRODUCING PERFLUORINATED PERFLUOROETHYLENE COPOLYMER CONTAINING SULPHONYL FLUORIDE FUNCTIONAL GROUPS Russian patent published in 2012 - IPC C08F2/00 C08F2/24 C08F2/34 C08F214/26 

FIELD: chemistry.

SUBSTANCE: method involves emulsion copolymerisation of tetrafluoroethylene and perfluoro-2-fluorosulphonyl ethoxy propyl vinyl ether, conducted at constant tetrafluoroethylene pressure in the presence of a radical initiator and an emulsion stabiliser - salt of perfluorocarboxylic acid C_nF_2n+1COONH₄, where n=7-9, involving a step for preliminary emulsion of perfluoro-2-fluorosulphonyl ethoxy propyl vinyl ether in an aqueous medium using a rotor-stator-type homogeniser at rotation speed of 8000-12000 rpm. Emulsion copolymerisation of tetrafluoethylene and perfluoro-2-fluorosulphonyl ethoxy propyl vinyl ether is carried out while stabilising the emulsion with an ammonium salt of perfluorocarboxylic acid C_nF_2n+1COONH₄, where n=7-9, whose concentration is reduced by 10-30%, by replacing its equivalent amount with a univalent salt of perfluoro-2-sulphonate ethoxy propyl vinyl ether, preferably an ammonium salt of perfluoro-2-sulphonate ethoxy propyl vinyl ether, while maintaining process conditions.

EFFECT: environmentally friendly method of producing a perfluorinated copolymer, specifically low consumption of a perfluorinated surfactant and low amount of washing water.

2 cl, 7 ex