Preparation and wide-frequency dielectric properties of (Ba_(0.5)S_(r0.4)Ca_(0.1))TiO_3/poly(vinylidene fluoride) composites

摘要

Poly(vinylidene fluoride) (PVDF) and (Ba_(0.5)S_(r0.4)Ca_(0.1))TiO_3 (BSCT) are used as matrix and fillers, respectively, to prepare polymer functional composites by solution casting with N, N-dimethyl formamide as a solvent. It is found that the addition of BSCT has significant influence on the crystallization, melting, and glass transition behaviors of the PVDF matrix. The dielectric properties of the BSCT/PVDF composites are studied over a wide frequency range from 100 Hz to 1 GHz and a wide temperature range from - 50℃ to 100℃ to explore the dependences of frequency and temperature. High dielectric constant (ε) up to 132 at 100 Hz and low dielectric loss (tan δ) down to 0.0045 at 1 GHz are achieved for the BSCT/PVDF composites. The obtained data of e are also theoretically fit by different models, and the modified Lichtenecker equation and Jayasundere-Smith equation show the best match.