Facile Grafting Modification of Poly(Vinylidene Fluoride-co-Trifluoroethylene) Directly from Inner CH=CH Bonds

To endow new functions to poly(vinylidene fluoride) (PVDF) based fluoropolymers and expand their application fields, chemical modification is a useful tool to achieve this goal. In this work, the grafting of varied vinyl monomers onto PVDF backbone is achieved via the radical polymerization process using poly(vinylidene fluoride-co-trifluoroethylene) bearing CH=CH double bonds (P(VDF-TrFE-DB)) as initiator, which is obtained by a controlled dehydrofluorination reaction of P(VDF-TrFE). The graft copolymerization is achieved under mild conditions, and the composition of the graft copolymers can be regulated by changing the reaction conditions. Moreover, the introduction of low-polar poly(methyl methacrylate) (PMMA) side chains can effectively adjust the crystallization and dielectric properties of P(VDF-TrFE). This work may offer a facile method for preparing PVDF-based graft copolymers.