Influence of sulfonyl fluoride monomers on the mechanism of emulsion copolymerization with the preparation of proton-conducting membrane precursors

•Different mechanisms of FS-141 and FS-81 emulsion copolymerization with TFE was analyzed on the synthesis topochemistry and polymers properties.•For the first time, the constants of the aqueous emulsion copolymerization of TFE with FS-141 and FS-81 were determined.•Comparison of water - emulsion synthesis courses of precursors of fluorine-containing ionomers of the Nafion or Aquivion type is carried out.•Presented results are necessary to control the chemical structure (composition) and molecular weight of polymers of Nafion and Aquivion types.