Dielectric behavior of electroactive fluorinate-based terpolymers

The dielectric and ferroelectric properties of the poly(vinylidene fluoride-trifluoroethylene-chlorotrifluoroethylene) terpolymers are studied in the temperature range 160-380 K. More attention was given to the dielectric loss in the dielectric spectra and the following results were obtained: (1) there are two dielectric polarization mechanisms, modes A and B, contributing to the majority of the dielectric permittivity; (2) by using the Cole-Cole plot method, precise relaxation rates of mode B can be obtained, which follow the Vogel-Fulcher relation with reasonable parameters, T-VF=similar to160+/-2 K, U-VF=similar to0.16+/-0.01 eV, nu(0)=1x10(12) Hz. The temperature where mode A occurs does not shift with the variation of frequency and a well-developed hysteresis loop is observed, indicating the existence of a normal "paraelectric-ferroelectric" transition in the terpolymer. (C) 2004 American Institute of Physics.