Microstructure and dielectric properties of Ba0.6Sr0.4TiO3/(acrylonitrile-butadiene-styrene)-poly(vinylidene fluoride) composites

Dielectric tunable composites are of importance to fabricate flexible electronic devices. However, the achievement of the desirable tunability is limited by the defects between polymer matrix and inorganic fillers, which results in high dielectric loss and low electric breakdown strength. In this contribution of Ba0.6Sr0.4TiO3/((acrylonitrile-butadiene-styrene)-(poly(vinylidene fluoride)) (BST/ABS-PVDF) composites, such limitation was overcome via surface-modifying fillers and a design of binary polymer matrix of ABS-PVDF. The ratio of ABS-PVDF matrix was initially optimized concerning microstructure and dielectric performances. The dielectric constant (from 13 to 27 at 1 kHz) and tunability (1.3 to 3.8% at 2 kV/mm) of BST/ABS-0.6PVDF were enhanced with BST content increasing from 10 to 40 vol%, while a low dielectric loss was maintained (similar to 0.09 at 1 kHz). BST/ABS-0.6PVDF with 40 vol% of BST exhibit a tunability of 20% at 16 kV/mm which doubles the commonly reported values and provides great promises for the dielectric devices such as phase shifter, tunable capacitors, and tunable antenna.