偶氮苯液晶嵌段共聚物薄膜自组装和光响应性研究进展

Progress in Self-assembly and Photo-responsiveness of Thin Films of Azobenzene-Based Liquid Crystalline Block Copolymers

偶氮苯液晶嵌段共聚物(LCBCP)是指分子中含有偶氮苯液晶高分子的一类嵌段共聚物(BCP)。偶氮苯LCBCP因结合了BCP微相分离的特性、液晶高分子的液晶相结构以及偶氮苯基元的光响应性,在纳米技术、信息存储以及光子学等领域备受研究者的关注。本文概述了近年来偶氮苯LCBCP薄膜自组装及光响应性的研究进展,阐述了排除体积效应和聚合物的表面偏析原理及其对偶氮苯LCBCP薄膜组装结构的影响,介绍了不同光源类型,包括线偏振光、紫外光以及非偏振光,对偶氮苯LCBCP薄膜组装结构的光调控,并简要介绍了偶氮苯LCBCP薄膜的功能化应用。此外,本文还讨论了现阶段偶氮苯LCBCP薄膜自组装研究方面的挑战,并对未来的研究前景进行了展望。

As a type of block copolymers(BCPs)containing an azobenzene-containing liquid crystalline(LC)block,azobenzene-based LC BCPs(LCBCPs),have attracted the attention of researchers in the fields of nanotechnology,information storage,and photonics,owing to the combination of the microphase separation of BCPs,the ordered LC structures of LC polymers,and the photo-responsiveness of azobenzene mesogens.In this review,the recent research progresses in self-assembly and photo-responsiveness of thin films of azobenzene-based LCBCPs are summarized.The principles of the excluded volume effect and the surface segregation are introduced.In addition,the influences of the excluded volume effect and the surface segregation on the self-assembled structures and the photo-induced orientation of azobenzene-based LCBCP films are also discussed.The light regulation with different light sources,including linearly polarized light,ultraviolet(UV)light and unpolarized light,on the self-assembled structures of azobenzene-based LCBCPs are described.In addition,the functional applications of azobenzene-based LCBCP films are also briefly introduced.Then,the challenges of current research on the self-assembly of thin films of azobenzene-based LCBCPs are discussed.Finally,the future research prospects of azobenzene-based LCBCPs are proposed.