Preparation and characterization of composites from Ba0.5Sr0.5TiO3 and polystyrene

Pure perovskite phase Ba0.5Sr0.5TiO3 powders were synthesized by facile co-precipitation using inexpensive TiOSO4 as the raw material. The post-calcining treatment was at the low temperature of 950 °C, which was about 200 °C lower than that of the conventional solid-state method. The effects of two types of precipitation agents on the properties of Ba0.5Sr0.5TiO3 powders were investigated, and cubic Ba0.5Sr0.5TiO3 particles were obtained at the optimal conditions. Afterwards, the obtained Ba0.5Sr0.5TiO3 ceramics were ground into fine ceramic powders, and modified with oleic acid to improve the compatibility with the polystyrene (PS) matrix. The modified ceramic powders were dispersed in PS via solution co-blending to obtain Ba0.5Sr0.5TiO3/PS composites. The structure and morphology of the Ba0.5Sr0.5TiO3/PS composites were characterized through X-ray diffraction (XRD), and scanning electron microscopy (SEM). The SEM images showed that the modified ceramic powders had good dispersion in the PS resin. Moreover, the dielectric and thermal properties of the Ba0.5Sr0.5TiO3/PS composites were investigated, and the results showed that the modified ceramic powders could enhance the dielectric constants and thermal stability of ceramic-polymer composites.