Affiliation:
1. Xi'an Modern Chemistry Research Institute Xi'an China
Abstract
The phased array antennas based on highly anisotropic nematic liuquid crystals have achieved rapid develepment in recent years. In this paper, super high birefringence liquid crystal compounds with bistolane core were synthesized and their properties were investigated. The bistolane compounds show high bifringence above 0.6 and high clearing points above 200°C. Based on these new liquid crystal compounds, a liquid crystal mixture with nematic temperature range of 5~164 ºC and birefringence of 0.5 was developed. At 19 GHz, the new liquid crystal mixture shows excellent dielectric properties, with dielectric anisotropy of 1.57, which is the highest value reported in known literature. The new liquid crystal mixture also has relatively low dielectric loss of 0.0089 and low viscoelastic coefficient of 17.6 ms/μm2.