低熔点三苯二炔类液晶合成及高频介电性能  

Synthesis and high frequency dielectric properties of low melting point triphenyl dialkyne liquid crystals

作　　者：兰庚 宋垚 王新杰 谌永强 张智勇 汪相如 吴胜莉 LAN Geng;SONG Yao;WANG Xin-jie;SHEN Yong-qiang;ZHANG Zhi-yong;WANG Xiang-ru;WU Sheng-li(Department of Chemistry and Environmental Engineering,Wuhan Polytechnic University,Wuhan 430023,China;School of Electronic Science and Engineering,University of Electronic Science and Technology,Chengdu 611730,China)

机构地区：[1]武汉轻工大学化学与环境工程学院,湖北武汉430023 [2]电子科技大学光电科学与工程学院,四川成都611730

出　　处：《液晶与显示》2023年第2期139-148,共10页Chinese Journal of Liquid Crystals and Displays

基　　金：国家装发部预研基金(No.61409230701);广东省重点领域研发计划(No.2019B010158001)。

摘　　要：液晶微波通信器件所用的液晶材料都是高双折射率(Δn)液晶化合物组合而成,这些化合物的熔点大多较高,使得液晶组合物的低温共熔点较高,不利于微波通信器件的发展。本文合成了8种侧乙基三苯二炔类液晶化合物,将其按照一定的比例配置成低温共熔点在-46℃的液晶组合物MA,并以此为液晶母体,将其与另外几种液晶混合,采用矩形谐振腔微扰法测试液晶组合物在微波频段(11~35 GHz)的介电性能,得到了在18 GHz时的介电常数值(Δεr)为0.954,最大介电损耗(tanδεr max)为0.0086,可满足微波用低熔点液晶材料的性能要求。The liquid crystal materials used for liquid crystal microwave communication devices are composed of high birefringence liquid crystal compounds,most of which have higher melting points,making the liquid crystal compositions have higher low temperature eutectic points,unfavorable for the development of microwave communication devices.In this paper,eight kinds of fluorinated ethyl triphenyldialkyne liquid crystal compounds were designed and synthesized,and configured them in a certain ratio to form a liquid crystal composition MA with a low-temperature co-melting point around-46℃.And we mixed them with several other liquid crystals and tested the dielectric properties of the liquid crystal compositions in the microwave frequency band(11~35 GHz)using the rectangular resonant cavity perturbation method,and obtained a dielectric constant value(Δεr)of 0.954 at 18 GHz,the maximum dielectric loss is(tanδεr max)0.0086,which meets the performance requirements of low melting point liquid crystal materials for microwave applications.

关 键 词：三苯二炔类液晶 低熔点 高双折射 合成 高频介电性能 

分 类 号：O753.2[理学—晶体学]