多官能Iniferter制备聚合物分散液晶膜及其含量对电光性能的影响  

PREPARATION OF POLYMER DISPERSED LIQUID CRYSTAL FILMS WITH MULTI-FUNCTIONAL INIFERTER AND ITS CONTENT EFFECT ON ELECTRO-OPTICAL PROPERTIES

作　　者：秦爱林[1] 汪映寒[1] 

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

出　　处：《高分子学报》2010年第7期870-875,共6页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号50773045);留学回国人员启动基金(基金号20071108-18-12)

摘　　要：采用可逆加成-断裂链转移(RAFT)、引发转移终止(Iniferter)活性自由基聚合法分步骤制备多官能Iniferter的大分子(RAFT-MI),并通过紫外光聚合诱导相分离法制备接枝共聚物为基体的聚合物分散液晶(PDLC)膜,研究了不同含量的RAFT-MI对PDLC膜的微观形貌、开态透光率、阈值电压(Vth)、饱和电压(Vsat)、对比度和记忆效应的影响.结果表明,当PDLC中的RAFT-MI含量从10%增加到30%时,开态透光率先增加,随后又逐渐降低,而Vth、Vsat逐渐降低,对比度先增加,然后又降低,记忆效应减弱.Polymer dispersed liquid crystal （ PDLC） films were prepared by photopolymerization induced phase separation （PIPS） with living macromolecule,synthesized by RAFT and iniferter in sequential steps.The living macromolecule with multi-iniferter was called RAFT-MI.The effects of RAFT-MI concentration on morphologies,transmittance,threshold voltage （Vth）,saturated voltage （Vsat）,contrast ratio and memory effect of PDLC were studied in detail.It was found that the liquid crystal droplet of PDLC increased at first and then decreased with the concentration of RAFT-MI varying from 10 wt% to 30 wt% ,while Vth decreased from 3.1 V to 1.5 V and Vsat decreased from 16 V to 6.8 V.On-state transmittance increased with the concentration of RAFT-MI varying from 10 wt% to 15 wt% ,and then decreased gradually due to the mismatch between the refractive index of liquid crystal and that of polymer matrix.In addition,contrast ratio increased from 2.2 to 4.0 at first and then decreased later;memory effect of PDLC was weakened.Therefore,the new combined method of living radical polymerization RAFT and Iniferter successfully improved the electro-optical properties of PDLC.

关 键 词：聚合物分散液晶 引发转移终止 可逆加成-断裂链转移 聚合诱导相分离 电光性能 

分 类 号：O631[理学—高分子化学]