EFFECT OF X-RAY-RADIATION ON THE STRUCTURE OF P(VDF TRFE) COPOLYMERS/

Structural changes in poly(vinylidene fluoride)-trifluoroethylene [P(V DF-TrFE)] copolymers caused by X-ray irradiation were investigated by molecular weight determination, EPR analysis, FTIR spectroscopy, gel c ontent, DSC thermal analysis, X-ray diffraction, and piezoelectricity measurements. Samples exhibit radiation-induced conductivity (RIG) due to the formation of radical ions. These radicals are generated by bon d cleavage, which could react, leading to structural changes such as o xidation, double bond formation, chain scission, and crosslinking. The increasing gel content with radiation dose indicated that crosslinkin gs of the polymer chains predominate. Irradiation on P (VDF-TrFE) caus ed the melting temperature, heat of fusion, and Curie temperature to d ecrease. These results are consistent with the partial destruction of crystalline domains. (C) 1997 John Wiley & Sons, Inc.