Thermally stimulated depolarization current in ferroelectric blends of copolymers of vinylidene fluoride with trifluoroethylene

摘要

Ferroelectric blends of vinylidene fluoride (VDF)/trifluoroethylene (TrFE) copolymer with different molar ratio of 56/44, 60/40, 63/37, 67/33, 70/30, 73/27 and 77/23 were fabricated by casting from methyl ethyl ketone solution. Thermally stimulated depolarization current (TSDC) of the samples has been measured using a modified thermal electric analyzer. Wide angle X-ray diffraction shows two peaks in the region of 2/spl theta/ = 18-20/spl deg/ for all the blends, which indicates that the blends have the same crystal lattice structures as the copolymers. DSC results show that the blends display the phase transition characteristics of both copolymers of 77/23 and 56/44. TSDC spectra of the blends also exhibits the characters of both components at different polarization temperatures.