溶液敏感型智能高分子薄膜  

Solution-sensitive intelligent polymer film

作　　者：胡梦婷 胡宏龙 袁丛龙 刘炳辉 李志英 郑致刚 HU Meng-ting;HU Hong-long;YUAN Cong-long;LIU Bing-hui;LI Zhi-ying;ZHENG Zhi-gang(School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237, China;School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China;School of Physics, East China University of Science and Technology, Shanghai 200237, China)

机构地区：[1]华东理工大学材料科学与工程学院,上海200237 [2]华东理工大学化学与分子工程学院,上海200237 [3]华东理工大学理学院,上海200237

出　　处：《液晶与显示》2021年第9期1205-1213,共9页Chinese Journal of Liquid Crystals and Displays

基　　金：国家自然科学基金(No.61822504,No.62035008,No.51873060);上海市青年科技启明星计划(No.17QA1401100);中央高校基本科研业务费项目。

摘　　要：本文采用胆甾相液晶诱导的方法制备手性多孔高分子薄膜,通过将向列相液晶与不同种类有机溶剂按照不同比例混合后填充入薄膜中以探究具有一维周期性螺旋结构的薄膜对溶液的敏感性。结果表明,基于聚合物网络的形状记忆效应和强大的界面锚定作用,聚合物薄膜对溶液都有响应并呈现出选择性反射。由于液晶与溶剂不同配比混合溶液产生的平均折射率差异,薄膜的反射带迁移可达140 nm。此外,不同溶剂与液晶按照相同的比例混合填充后重构样品的反射带差异也较为明显。具体来说,所选用的乙酸丁酯溶剂的折射率仅比乳酸丁酯溶剂的折射率小0.03,但薄膜的反射带中心波长却相对红移约20 nm,进一步的实验表征和分析表明,这一现象归因于聚合物薄膜的溶胀度会随着溶剂与聚合物薄膜两者之间的溶度参数差值而改变,即溶剂与聚合物的溶度参数越接近,溶剂越容易扩散进入聚合物薄膜中,并使其体积膨胀,从而螺距产生更大的拉伸,由此导致反射带发生相对红移。因此,这种柔性反射膜是具有溶液敏感性的。In order to explore the sensitivity of the polymer film with one-dimensional periodic helical structure to the solution,a manner molded by cholesteric liquid crystal(CLC)is utilized for producing the chiral porous polymer film,and then the research is carried out through permeating the solution mixed by diverse proportions with nematic liquid crystal and different organic solvents into the film.The results indicate that the polymer film responds to the solution and exhibits selective reflection,which is attributed to the shape memory effect and the strong interface anchoring force of the polymer network.The reflection band shifts up to 140 nm owing to the difference in average refractive index of mixed solutions with different ratios of liquid crystal and solvent.In addition,it is also obvious that the type of solvent makes difference to the reflection band of the film when the solvent is mixed with the same proportion of liquid crystal.Specifically,the refractive index of the selected butyl acetate solvent is only 0.03 lower than that of butyl lactate,however,the central wavelength of the reflection band is approximately 20 nm larger than that of butyl lactate.Further experimental characterization and analysis manifest that the swelling degree of the polymer film varies with the discrepancy of solubility parameter between solvents and the polymer film,that is,the closer the solubility parameters are,the easier it is for the solvent to diffuse into the polymer and make its volume expand,resulting in the pitch elongation and consequent redshift of the reflection band.Therefore,the flexible reflective film is solution sensitive.

关 键 词：胆甾相液晶 螺旋结构 聚合物薄膜 溶液敏感性 

分 类 号：O753.2[理学—晶体学]