Toward Optimized Process Parameters for Ferroelectricity and Piezoelectricity in P(VF2-VF3) Copolymers
Abstract
The combined effects of uniaxial orientation and annealing on the ferroelectric and piezoelectric response in two compositions of poly(vinylidene fluoride-trifluoroethylene) random copolymers have been studied. Results show that although a non-ferroelectric mixture of phase-I and phase-II material are formed when the 73:27 and the 80:20 molar compositions are quenched from the melt, both are transformed to almost pure ferroelectric phase-I material when samples are uniaxially oriented to draw ratios of 6:1 and 5:1 respectively. The corresponding ferroelectric and piezoelectric responses increased as draw ratio increased. When drawn films were annealed before poling, significant enhancement in remanent polarization, Pr, for both compositions were observed when they were compared with their unannealed counterparts. These results provide foundation for the optimization of P(VF2-VF3) copolymer electroprocessing. Drawing of previously non-ferroelectric melt-quenched films followed by annealing yields larger Pr and d31 than those obtained by either drawing or annealing only.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2002
- Bibcode:
- 2002APS..MARD11013C