Synthesis and microstructure of a novel graft copolymer from poly(vinylidene fluoride–chlorotrifluoroethylene–trifluoroethylene)

A novel graft copolymer of poly(vinylidene fluoride–chlorotrifluoroethylene–trifluoroethylene)-graft-poly(6-((4-cyano-4-biphenyl)oxy) hexyl methacrylate) (P(VDF-CTFE-TrFE)-graft-PCBHM) using P(VDF-CTFE-TrFE) as the initiator was successfully synthesized via atom transfer radical polymerization. It was found that the crystallinity of resultant graft copolymer increased slightly after grafting from the P(VDF-CTFE-TrFE), and the crystalline regions in the graft copolymer contained more (β phase which has all-trans chain conformation) trans chain conformation. Upon the introduction of PCBHM side chains, the thermal stability of the graft copolymer was lower than that of pristine terpolymer, but the storage modulus was enhanced significantly, which is beneficial for breakdown field-strength enhancement, and dielectric properties simultaneously decreased.