Synthesis and characterization of polyacrylonitrile-grafted copolymers based on poly(vinylidene fluoride)

Abstract

Grafted poly(vinylidene fluoride) (PVDF)-based copolymers attract great attention due to their tunable ferroelectric and dielectric characteristics, which gives great perspectives for electronic applications. In this work, two strategies for polyacrylonitrile-grafted PVDF-based copolymers synthesis, namely single electron transfer radical polymerization (SET-LRP) and photoinduced Cu(II)-mediated reversible deactivation radical polymerization (RDRP) were investigated, their advantages and shortcomings are discussed. Using these methods two series of poly(vinylidene fluoride-co-chlorotrifluoroethylene)-grafted-polyacrylonitrile p(VDF-co-CTFE)-g-PAN and poly(vinylidene fluoride-co-trifluoroethylene-co-chlorotrifluoroethylene)-grafted-polyacrylonitrile p(VDF-co-TrFE-co-CTFE)-g-PAN with different PAN content were prepared. Important characteristics of the grafted PVDF-based copolymers such as phase behavior, thermal stability, and dielectric properties were investigated, and impacts of the macromolecular backbone type, as well as the content of grafted PAN on these properties, are discussed. It was shown that PAN incorporation leads to significant dielectric properties change since the dielectric permittivity of PAN-grafted copolymers is twice higher in comparison to the pristine copolymers. The crucial impact of PAN grafting onto PVDF-based copolymers backbone on their phase, thermal and dielectric behavior is demonstrated.

Keywords

• polymer synthesis, molecular engineering
• fluoropolymer
• poly(vinylidene fluoride)-based copolyme
• grafted polymer
• atrp polymerization