Effect of gamma-ray radiation on structure of P(VDF/TrFE) 80/20 mol% copolymers

The gamma -ray irradiation effect on poly(vinylidene-trifluoroethylene) 80/ 20 mol% copolymers was studied. It is found that the irradiation results in the cross-linking in the amorphous area and the carbon-carbon double bond in the copolymer due to dehydrofluorination. The thermal analysis (DTA) dat a indicate that the irradiation down shifts both the melting temperature an d the phase transition temperature, and the irradiation also reduces the cr ystallinity. It is found that the size of the crystal regions in the copoly mer decreases during the irradiation and that the lattice space expanses wi th the irradiation. The crystal regions with a reduced size might response for the excellent electromechanical properties observed in the irradiated c opolymer. (C) 2001 Elsevier Science Ltd. All rights reserved.