锥光干涉法表征偶氮苯侧链液晶聚合物的光致取向  

Orientational Morphology Characterization of Azobenzene Containing Side-chain Liquid Crystalline Polymer by Conoscopic Polarized Microscopy

作　　者：刘剑[1] 王明乐[1] 李剑[1] 钟何金[1] 郭刚[1] 

机构地区：[1]西南科技大学四川省非金属复合与功能材料重点实验室-省部共建国家重点实验室培育基地,绵阳621010

出　　处：《高分子通报》2011年第8期85-90,共6页Polymer Bulletin

基　　金：国家自然科学基金资助项目(基金号20774076)

摘　　要：采用偏光显微镜在平行光和锥光条件下对液晶聚合物膜内分子的取向排列状态进行了研究,不同取向状态的膜由线偏振光或圆偏振光照射偶氮苯侧链液晶聚合物得到。结果表明,液晶聚合物膜采用线偏振光照射时,偶氮苯介晶基元沿面排列,形成单相畴面内取向态。该取向态的锥光干涉图为位于视场中心的粗黑十字,旋转载物台小于10°,该干涉图即完全退出视场。采用圆偏振光照射时,介晶基元沿光入射方向取向,形成的锥光干涉图消光中心与取向光的倾斜方向呈线性关系逐渐偏移视场中心。同时,圆偏振光照射时介晶基元有面内取向和面外取向两种排列方式存在。圆偏振光垂直照射取向后的薄膜在Tg以上温度退火处理后,面内取向的分子重新发生面外取向,液晶聚合物膜呈现单轴、垂直光轴切面的锥光干涉图样。The transmittance tests and the polarized microscopy were used to investigate the orientational structures of azobenzene-containing side-chain liquid crystalline polymer upon linearly polarized light（LPL）and circularly polarized light （CPL）irradiation. The results suggest an in-plane arranged single-domain order phase was achieved upon the LPL irradiation, which showed a black cross interference figure. The figure disappeared upon less than 10~ rotation of the stage. As a contrast,CPL pumped film showed centered conoscopic interference figure upon a perpendicular light irradiation. The off-center distance of interference figures depends on the incident angle of the CPL beams. The annealed film showed a fixed conoscopic image with its optical axis perpendicular to the film plane, suggesting that oriented azobenzene mesogen belongs to the uniaxial type of anisotropic unit.

关 键 词：锥光干涉图 液晶聚合物 取向 

分 类 号：O631.24[理学—高分子化学]