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The radical solution copolymerization of hexafluoropropylene, chlorotrifluoroethylene (CTFE), vinylidene fluoride, and tert-butyl-α-trifluoromethylacrylate with different monomers bearing isocyanato groups such as allyl isocyanate, 3-isopropenyl-α,α′-dimethylbenzyl isocyanate (m-TMI), and 2-isocyanatoethyl methacrylate, initiated by 2,5-bis(tert-butylperoxy)-2,5-dimethylhexane were studied. Several of these radical copolymerizations were not successful in contrast to that of CTFE with m-TMI, although m-TMI monomer does not homopolymerize under radical initiation. The resulting poly(CTFE-co-m-TMI) copolymers were characterized by 1H and 19F nuclear magnetic resonance and Fourier transform infrared spectroscopy and their compositions assessed by elemental analysis. The reactivity ratios of both comonomers were determined by linearization methods of Fineman-Ross, Kelen-Tudos for low conversions of monomers, and by the extended Kelen-Tudos method for high monomer conversions. The average values of the monomer reactivity ratios, rCTFE and rm-TMI, were 0.076 and 0.034 at 130 °C, respectively, depending on these monomer conversions and the applied methods of calculation. In all cases, rCTFE × rm-TMI product was close to zero, which indicates that poly(CTFE-co-m-TMI) copolymers exhibit a high tendency toward alternation. This was also confirmed by the Igarashi's theory which revealed a high content of CTFE-m-MTI heterodyads. The Q and e values for m-TMI monomer were also assessed (Qm-TMI = 0.007 and em-TMI = 0.99). As well as this kinetics of copolymerization, several properties of the obtained fluorofunctional copolymers such as molecular weights (ranging from 1500 to 8200 g mol−1), molecular weight distributions (from 1.2 to 2.1) were also investigated. Their thermal properties revealed satisfactory thermal stability (higher than 250 °C). © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2681–2697, 2010

International audience; The radical co- and terpolymerization of perfluoro(4-methyl-3,6-dioxaoct- 7-ene) sulfonyl fluoride (PFSVE) with 1,1-difluoroethylene (or vinylidene fluoride, VDF or VF2), hexafluoropropene (HFP), chlorotrifluoroethylene (CTFE), and bromotrifluoroethylene (BrTFE) is presented. Although PFSVE could not homopolymerize under radical initiation, it could be copolymerized in solution under a radical initiator with VDF, while its copolymerizations with HFP or CTFE led to oligomers in low yields. The terpolymerizations of PFSVE with VDF and HFP, with VDF and CTFE, or with VDF and BrTFE also led to original fluorinated terpolymers bearing sulfonyl fluoride side-groups. The conditions of co- and terpolymerization were optimized in terms of the nature and the amount of the radical initiators, of the nature of solvents (fluorinated or nonhalogenated), and of the initial amounts of fluorinated comonomers. The different mol % contents of comonomers in the co- and terpolymers were assessed by 19F NMR spectroscopy. A wide range of co- and terpolymers containing mol % of PFSVE functional monomer ranging from 10 to 70% was produced. The kinetics of copolymerization of VDF with PFSVE enabled to assess the reactivity ratios of both comonomers: rVDF ¼ 0.57 6 0.15 and rPFSVE ¼ 0.07 6 0.04 at 120 8C. The thermal and physicochemical properties were also studied. Moreover, the glass transition temperatures (Tgs) of poly(VDF-co-PFSVE) copolymers containing different amounts of VDF and PFSVE were determined and the theoretical Tg of poly(PFSVE) homopolymer was deduced. Then, the hydrolysis of the SO2F into SO3H function was investigated and enabled the synthesis of fluorinated copolymers bearing sulfonic acid functions.