Intermediate Structure at the Ferro-to-Paraelectric Phase Transition of VDF/TrFE Copolymer (54/46 mol%)

Abstract
Precise X-ray diffraction measurements for a VDF/TrFE copolymer (54/46 mol%) have been conducted. The computer profile analysis suggests that the crystal structure at room temperature is a mixed one of ferroelectric and paraelectric structures, with increasing temperature the transition from a ferroelectric structure to a paraelectric one occurs passing through an intermediate structure in the ferroelectric phase transition region. This three-component model explains well the temperature variation of the specific volume observed for a bulk specimen.