Iodine transfer polymerization (ITP) of vinylidene fluoride (VDF) in the presence of two chain transfer agents (CTA, such as C6F13I and HC2F4CH2I) is presented. Various experimental conditions in terms of the nature of the radical initiators, time, temperature and initial [initiator]0/[VDF]0 and [CTA]0/[VDF]0 molar ratios influenced the yield of the reaction, the obtained average degree of polymerization in number, n, of PVDF−I, the defect of VDF-chaining, and the CX2I functionality (where X = H or F). The microstructures of these produced PVDF−I oligomers were characterized by 1H and 19F NMR spectroscopy which enabled one to assess the n values and to quantify the head-to-head or tail-to-tail defects of VDF-chainings. A low amount of defect of chaining in PVDF−I when C6F13I was used in contrast to a higher content from HC2F4CH2I. These PVDF−Is exhibited a favored −CH2CF2I functionality from the former CTA which was not observed in the latter one. A good agreement between the targeted and the obtained n values was noted for ITP of VDF in the presence of C6F13I (representative of normal addition) whereas that carried out from HC2F4CH2I (representative of inverse addition) led to experimental n values higher than the targeted ones in all cases. A low conversion of HC2F4CH2I was observed in contrast to that of C6F13I, which shows a better efficiency as the transfer agent.

Poly(vinylidene fluoride)-g-poly(styrene) graft copolymers (PVDF-g-PS) were synthesized by the “grafting from” method from a PVDF macroinitiator bearing bromine side groups. This fluorinated macroinitiator was obtained from the radical copolymerization of VDF with 8-bromo-1H,1H,2H-perfluorooct-1-ene (BDFO), and then it was used in the atom transfer radical polymerization (ATRP) of styrene initiated by CuIBr/1,1,4,7,10,10-hexamethyltriethylenetetramine (HMTETA) catalyst. First, the synthesis of a model poly(styrene) was investigated starting from 1-bromoperfluorooctane (C8F17Br) as the initiator to check the reactivity of −CF2−Br in ATRP process. Successful ATRP of styrene in the presence of 1-bromoperfluorooctane was observed from a kinetic study and NMR spectroscopy, and the activation rate constant of this initiator (k act = 35 × 10-3 M-1 s-1 at 35 °C in acetonitrile) was assessed for the first time. In a second part, ATRP of styrene was also studied from poly(VDF-co-BDFO) copolymers as the macroinitiators, taking into account:  (i) the effect of the polymerization temperature, (ii) the ligand concentration in the ATRP catalyst, and (iii) the amount of solvent vs the conversion of poly(styrene). The formation of graft copolymers was confirmed by size exclusion chromatography and by 1H and 19F NMR spectroscopies. Interestingly, the linear dependences of both the evolutions of ln([M]0/[M]) vs time and of the molecular weights of the resulting graft copolymers vs the styrene conversions, and the decrease of their dispersity indexes vs the styrene conversions evidenced the controlled behavior of that graft polymerization.

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