Bistable electro-optical switching for (liquid crystalline polymer)/(low molecular weight liquid crystal) composite system
Bistable electro-optical switching for (liquid crystalline polymer)/(low molecular weight liquid crystal) composite system
复制标题
(液晶聚合物)/(低分子液晶)复合系统的双稳态电光切换
DOI：
10.1002/pat.1990.220010503
复制
发表时间：
1990
影响因子：
3.4
通讯作者：
T. Kajiyama
中科院分区：
文献类型：
--
作者：
H. Kikuchi;S. Moritomi;J. Hwang;T. Kajiyama
采用溶剂浇铸法制备了一系列由液晶聚合物(LCP)和低分子液晶(LMWLC)组成的薄膜。LMWLC在各向同性和介晶态的LCP浓度范围内是相容的。在LCP质量分数大于50%的范围内，复合体系形成近晶相。对于LCP和LMWLC组成的二元复合材料的近晶相，基于光散射的可逆和双稳态电光效应被识别出来。在施加交流电源的情况下，出现光散射状态。低于阈值频率(Fc)的电场。此外，交流电源的应用。高于Fc的电场使透射光强度增大。这种现象是由两种效应共同引起的：一种是基于介电各向异性的电场效应，另一种是基于主链电流体运动的电流效应。在近晶中间相的情况下，即使去掉电场(记忆效应)，混浊和透明状态也保持不变。
A series of thin films composed of liquid crystalline polymer (LCP) and low molecular weight liquid crystal (LMWLC) was prepared by a solvent-casting method. LMWLC is miscible over a whole range of LCP concentrations in isotropic and mesomorphic states. The composite system formed a smectic phase in a LCP weight fraction range above 50%. Reversible and bistable electro-optical effects based on light scattering were recognized for a smectic phase of the binary composite composed of LCP and LMWLC. A light scattering state appeared in the case of application of an a.c. electric field below a threshold frequency (fc). Furthermore, application of an a.c. field above fc made the transmission light intensity increase. Such phenomena were induced in conjunction with the two types of effect: one is an electric field effect based on the dielectric anisotropy of the mesogenic side chain; and the other is an electric current effect based on the electrohydrodynamic motion of the main chain. In the case of a smectic mesophase, the turbid and transparent states remained unchanged, even though the electric field is removed (memory effect).