单体烷基链长度对聚合物分散液晶膜电光性能的影响  

Effects of monomer alkyl chain length on electro-optical properties of polymer dispersed liquid crystal film

作　　者：曾腾 何韬钰 汪映寒[1] ZENG Teng;HE Tao-yu;WANG Ying-han(State Key Laboratory of Polymer Materials and Engineering,College of Polymer Science and Engineering, Sichuan University, Chengdu 610065, China)

机构地区：[1]四川大学高分子科学与工程学院高分子材料与工程国家重点实验室,四川成都610065

出　　处：《液晶与显示》2021年第10期1362-1368,共7页Chinese Journal of Liquid Crystals and Displays

基　　金：国家自然科学基金(No.50973067,No.51173115)。

摘　　要：聚合物分散液晶(PDLC)膜是微米尺寸的液晶微滴嵌入连续聚合物基体中形成的薄膜。利用点击化学方法制备PDLC可避免传统光聚合诱导相分离法造成的染料分解等问题。本研究用4种不同烷基链长度的聚乙二醇二丙烯酸酯(PEGDA)作为原料,利用硫醇-烯点击化学反应和硫醇-异氰酸酯偶联反应合成了PDLC膜,研究烯烃单体的烷基链长度对PDLC膜电光性能的影响。结果表明,随着体系中烯烃烷基链长度增加,阈值电压(Vth)、饱和电压(Vsat)和对比度(CR)下降,但关态透光率(Toff)和开态透光率(Ton)上升。通过选用烷基链长度适当的烯烃可以制得综合电光性能良好的PDLC膜。Polymer dispersed liquid crystal(PDLC)is a thin film formed by liquid crystal(LC)droplets embedded in a continuous polymer matrix in the form of micron-sized droplets.The use of click chemistry method to prepare PDLC can avoid the problems of dye decomposition caused by traditional photopolymerization-induced phase separation.In this study,four polyethylene glycol diacrylates(PEGDA)of different alkyl chain lengths were used as raw materials to synthesize PDLC films through thiol-ene click reaction and thiol-isocyanate coupling reaction,to study the effects of different alkyl chain length olefin monomers on the electro-optical properties of PDLC films.The results showed that as the chain length of olefin alkyl chain in the system increased,the threshold voltage(Vth),saturation voltage(Vsat)and contrast ratio(CR)decreased,while off-state transmittance(Toff)and on-state transmittance(Ton)increased.By selecting olefin with appropriate alkyl chain length,PDLC films with good electro-optical properties can be prepared.

关 键 词：聚合物分散液晶 点击化学 单体烷基链长度 电光性能 

分 类 号：O753.2[理学—晶体学]