Development of Flexible and Large area Liquid Crystal Display Devices

由聚合物和低分子量液晶（LC）组成的复合材料是用于制备诸如显示器和电控光闸的电光器件的有前途的材料。生产复合材料的实用方法是通过聚合物前体（交联剂LC）的初始混溶溶液的光聚合诱导相分离。复合材料的性能很大程度上取决于聚合物网络和液晶畴的最终形态。其形貌由制备过程中的相分离热力学和动力学共同决定。本研究以乙烯基醚共聚物和液晶为复合材料，通过聚合物/液晶的光聚合反应，使聚合物和液晶发生双连续相分离，从而制备出大面积的柔性液晶显示器。传统的聚合物/液晶复合材料的多路复用性能较差，而液晶显示器的多路复用性能较差。本研究的主要目的是利用聚合物/液晶复合材料的光致聚合反应，制备出一种新型的液晶显示器 ...更多信息 这是因为光透射-电压曲线的陡度不够。对于<80>常规的（聚合物/L）复合材料，陡度的典型量值V_ /V_5大于1.4，其中V_<80>和V_5分别为80%透射电压和5%透射电压。通过优化单体组成、光辐射温度、光辐射强度等条件，制备了乙烯基醚共聚物/液晶复合材料，其响应曲线V_<80>/V_5在1.25 ~ 1.35之间，在8倍倍率下，光学对比度可达30-70。从光散射特性、介电性能、形态流变学、聚合动力学和相分离动力学等方面研究了其电光响应机理。在（单体/LC）混合物溶液的光聚合过程中，旋节分解或粘弹性相分离成富含聚合物和富含LC的相与聚合物网络的发展之间的时间是控制电光性能的主导因素。少

Composite materials consisting of polymers and low molecular weight liquid crystals (LCs) are promising materials for preparation of electro-optical devices such as displays and electrically controllable light shutters. A practical method of producing composites is by photopolymerization induced phase separation of an initially miscible solution of polymer precursor, crosslinker LCs. The performance of the composites strongly depends on the final morphology of the polymer network and the LC domains. The morphology is determined by both thermodynamics and kinetics of phase separation during the preparation processes. In this stud novel composite materials consisting of vinyl ether copolymers and LCs were prepared to develop a large-area and flexible display for addressing by simple multiplex electrodes.A bicontinuous phase separation of polymer and LCs was induced by photopolymerization of monomers solved in L Conventional (polymer/LC) composites have been poor in the multiplexing capab … More ility because of insufficient steepness of the opti transmission-electric voltage curve. A typical magnitude of steepness, V_<80>/V_5 is larger than 1.4 for conventional (polymer/L composites, where V_<80> and V_5 are 80 % transmittance voltage and 5 % transmittance voltage, respectively. In contrast, an extrem steep response was achieved for novel (vinyl ether copolymer/LCs) composites by optimizing the monomer component, the phcirradiation temperature the photo-irradiation intensity and so on. The magnitude of V_<80>/V_5 ranged 1.25 to 1.35 which can give optical contrast ratio of 30-70 at the multiplex level of 8. The mechanism of the electro-optical response was investigated based light scattering characteristics, dielectric properties, morphology rheology, polymerization kinetics and phase-separation kinetics. The timing between the occurrence of the spinodal decomposition or the viscoelastic phase separation into polymer rich and LCs-rich pha and the development of polymer network during photopolymerization of (monomers/LCs) mixture solution was a dominant factor control the electro-optical properties. Less