Significantly improved high dielectric MWCNTs filled PVDF/PS/HDPE composites via constructing double bi-continuous structure

Abstract

Multi-layer composites with vastly difference in electrical properties for each layer are a promising candidate to design high dielectric materials, showing a tremendous promise on dielectric applications. But fabrication of these dielectric materials is relatively complicated, and unsuitable for large-scale production. Herein, a novel dielectric poly (vinylidene fluoride)/polystyrene/high density polyethylene (PVDF/PS/HDPE) composite constructed via tri-continuous structure were designed. And via variation PS concentration to control the compatibilizer effect of PS phase, a smaller PS phase size has been obtained and this composite finally exhibits a double bi-continuous morphology structure. For this double bi-continuous PVDF/PS/HDPE composite, a better dispersion of MWCNT particles increases the density of interfacial charge enrichment, and the increase of the specific surface area of the interfacial layer increases the number of enriched charges, which make the interfacial polarization increase most significantly compared with the other composites. Thus, a high-performance dielectric PVDF/PS/HDPE composite with high ε′ and low tan δ have been realized.