Electromechanical properties and molecular conformation in P(VDF-TrFE) based terpolymer

The recent discovery of high electromechanical performance in high-energy electron irradiated P(VDF-TrFE) copolymers opens a new avenue for developing high performance electroactive polymers. From basic materials consideration, it is expected that one can achieve high electromechanical performance by means of nonirradiation approach, such as introducing ter-monomer to form PVDF based terpolymer. The basic requirement for the ter-monomer is discussed in order to achieve a high electromechanical performance in P(VDF-TrFE) based terpolymer. Based on the conclusion, P(VDF-TrFE-CFE) terpolymer has been synthesized and the experimental results indicate that the terpolymer exhibits better electromechanical performance compared with irradiated copolymers. For example, both the electric induced strain and Young's modulus in P(VDF-TrFE-CFE) terpolymer could be higher than that in irradiated copolymers. X-ray diffraction, DSC and FTIR were employed to determine the structure and molecule conformation. Furthermore, a serious theoretical simulation was carried out for P(VDF-TrFE) based terpolymers with different termonomers. The results show that indeed the terpolymer with CFE favors gauche conformation, consistent with the experimental results.