摘要
以小分子蓝相小板块液晶(反,反)-4-丙基-4′-乙烯基双环己烷(3HHV)为液晶基元,通过与聚甲基氢硅氧烷进行硅氢加成反应,合成了一种新的聚硅氧烷侧链液晶,产率为78%。通过傅立叶变换红外光谱(FT-IR)和核磁共振谱(1 H-NMR)对单体和聚合物进行结构表征,证实了单体中双环己烷结构和双键的存在,说明了硅氢加成反应近于完全;通过热失重分析仪(TGA)分析了单体和聚合物的耐热性;通过差示扫描量热仪(DSC)、热台偏光显微镜(POM)和X射线衍射仪(XRD)对单体和聚合物的液晶行为进行分析,证实了二者液晶性的存在,且聚合物的介晶区间相比于单体提高了98.4℃,同时POM分析还揭示了合成的液晶高分子在降温过程中呈现出的罕有的聚合物近晶A球粒织构。
A new type of side-chain liquid-crystalline polysiloxanes （SCLCPs） was synthe- sized by graft polymerization, using （trans, trans）-4-propyl-4＇-vinyl-bicyclohexane （3HHV） with platelet texture of a blue phase as mesogenic monomer, and the production rate is 78%. The bicyclohexane structure and double bond of monomer and the hydrosilylation reaction in monomer and polymer were confirmed by characterizing the chemical structure of liquid crystal monomer and polymer by means of Fourier transform infrared spectroscopy and hydrogennuclear magnetic resonance spectra. Liquid crystal behavior of monomer and polymer were analyzed by differential scanning calorimetry, polarizing optical microscopy and X-ray diffraction. The mesophase temperature range of polymer was increased by 98.4°C comparing with the mesophase temperature range of monomer. Meanwhile, spherulite texture of polymeric smectic A phase of liquid crystal polymer was revealed in the cooling cycle by polarizing optical microscopy, and this texture was so uncommon that can hardly be found in the liquid crystalline polymers.
出处
《液晶与显示》
CAS
CSCD
北大核心
2011年第4期437-442,共6页
Chinese Journal of Liquid Crystals and Displays
基金
陕西省教育厅科研计划基金资助项目(No.2010JK680)
西安科技大学培育基金资助项目(No.200815)
关键词
聚硅氧烷
液晶聚合物
蓝相小板块织构
聚合物近晶A球粒织构
polysiloxanes
liquid crystalline polymers
platelet texture of a blue phase
polymeric smectic A spherulite texture
