Dielectric Properties of Barium (Strontium) Titanate/ Polybenzoxazine Composites with 0-3 Connectivity for Electrical Applications

摘要

Ceramic-polymer composite with 0-3 connectivity were fabricated from barium strontium titanate (BST) and polybenzoxazine. Effect of ceramic content, temperature and frequency of the composites were discussed. BST ceramic powders were prepared by sol-gel process. The amount of ceramic content in polybenzoxazine matrix was varied from 30 - 80 wt% in order to investigate the effect of ceramic contents on dielectric behavior of the composites. It was found that composite dielectric constant increase with increasing ceramic contents. By adding 80 wt% (48 vol%) of ceramic fillers, the dielectric constant was as high as 28. And, the dielectric constants of the composites are nearly stable with frequency range of 1 kHz - 10 MHz and temperature range of 20-130°C. The measured dielectric constant can fit well with Yamada model indicating 0-3 connectivity.