Enhanced dielectric thermal stability and permittivity of flexible composite films based on BaTiO₃ nanoparticles highly filled PVDF/PAN blend nanofibrous membranes

Abstract

Polymer film capacitors with high stability and reliability at elevated temperatures are promising for next‐generation power electronic systems and hybrid electric vehicles. In this work, sandwich‐structured composite films with good dielectric thermal stability were fabricated based on hybrid membranes of poly(vinylidene fluoride)/polyacrylonitrile blend nanofibrous skeleton highly filled with BaTiO 3 nanoparticles. Composite films with 64.7 vol% BaTiO 3 nanoparticles in the core layer exhibited high permittivity (38.1) and low loss (0.046) at 1 kHz and room temperature, and the dielectric permittivity and loss were only slightly increased to 41.5 and 0.08, respectively, at 120°C. Good dispersion and high loading of BaTiO 3 nanoparticles in the composites films contributed to enhanced dielectric thermal stability and permittivity. Moreover, the composite films showed good flexibility, which could be ascribed to its sandwich‐structure. Our work paves a generic way to fabricate flexible composite films with excellent dielectric thermal stability via high loadings of ceramic nanoparticles. POLYM. COMPOS., 39:E1841–E1848, 2018. © 2018 Society of Plastics Engineers