Reversible Controlling the Supramolecular Chirality of Side Chain Azobenzene Polymers: Chiral Induction and Modulation
Reversible Controlling the Supramolecular Chirality of Side Chain Azobenzene Polymers: Chiral Induction and Modulation
复制标题
可逆控制侧链偶氮苯聚合物的超分子手性：手性诱导和调制
DOI：
10.1002/marc.202100904
复制
发表时间：
2022-02-13
影响因子：
4.6
通讯作者：
Li, Wei
中科院分区：
文献类型：
--
作者：
Li, Guangyao;Xu, Mingcong;Li, Wei
手征性是自然界的一种基本结构，通过可行的技术手段诱导和可逆地调控超分子手征性，对于设计新型手征性智能材料具有重要价值。本文合成了两种偶氮苯侧链聚合物（不含间隔基的偶氮-PMA 0和含6个间隔基的偶氮-PMA 6），间隔基的长度和偶氮苯生色团的长度对手性传递和调制起着至关重要的作用。Azo-PMA 0（非晶相）的超分子手性排列可以通过聚合物链的偶氮基团之间的超分子相互作用驱动的450 nm圆偏振光在多个循环中完全控制和可逆调制，吸收不对称因子（g）值为0.0019。在偶氮发色团的反-顺异构化过程中，紫外光和热退火处理也可以可逆地调制偶氮-PMA 6（液晶态）的手性光学性质，g值在0-0.038之间变化。基于侧链偶氮苯聚合物的可逆手性诱导和调制的成功构建为设计光开关功能材料奠定了基础。
Chirality represents a fundamental structure in nature and the induction and reversible modulation of supramolecular chirality with feasible techniques is of great value in the design of new chiroptical smart materials. Herein, two kinds of azobenzene side-chain polymers (without spacer: Azo-PMA0; with 6 spacers: Azo-PMA6) are synthesized, the length of spacer and azobenzene chromophores play a vital role in chirality transfer and modulation. The supramolecular chiral arrangement of Azo-PMA0 (amorphous phase) can be completely controlled and reversibly modulated over multiple cycles by 450 nm circularly polarized light driven by the supramolecular interaction between azo groups of polymer chains, with an absorption dissymmetry factor (g) value of 0.0019. The chiroptical properties of Azo-PMA6 (liquid crystal state) can also be reversibly modulated by UV light and thermal annealing treatment during trans-cis isomerization of azo chromophore, with the g-value changes from 0-0.038. The successful construction of reversible chiral induction and modulation based on side chain azobenzene polymers may pave the way for designing photo-switchable functional materials.