Ceramic-Polymer Composites with Low Dielectric Loss for Microwave Antennas and Wireless Sensors

摘要

The low dielectric loss ceramic-polymer composites were prepared by extrusion processing technique with high density polyethylene (HDPE) as matrix and high permittivity ceramic powder in BaO-Nd_2O_3-TiO_2 (BNT) system as filler. The dielectric response in microwave frequency range was characterized, and the experimentally observed dielectric properties were compared with the theoretical models. The relative permittivities of the composites vary from 3 to 10 with the increase in the volume fraction of BNT filler from 10 to 40 vol%. The dielectric losses of all composites are less than 0.001. For 40 vol% ceramic loaded HDPE, the relative permittivity of 10 and loss tangent of 0.0007 at 7 GHz were obtained. The BNT-HDPE composites are promising materials for microwave dielectric antenna applications.