Physio-and chemo-dual crosslinking toward thermoand photo-response of azobenzene-containing liquid crystalline polyester

作     者：Hai-Yi Zhong Li Chen Xiao-Min Ding Rong Yang Yu-Zhong Wang 钟海艺;陈力;丁晓敏;杨荣;王玉忠

作者机构：Center for Degradable and Flame-Retardant Polymeric MaterialsCollege of ChemistryState Key Laboratory of Polymer Materials EngineeringNational Engineering Laboratory of Eco-Friendly Polymeric Materials（Sichuan）Sichuan UniversityChengdu 610064China College of PharmacyGuangxi University of Chinese MedicineNanning 530299China School of Materials Science and EngineeringChangzhou UniversityChangzhou 213000China 

出 版 物：《Science China Materials》 (中国科学（材料科学（英文版）)

年 卷 期：2018年第61卷第9期

页      面：1225-1236页

核心收录：

学科分类：081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 070205[理学-凝聚态物理] 070305[理学-高分子化学与物理] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0703[理学-化学] 0702[理学-物理学] 

基　　金：supported by the National Natural Science Foundation of China (51721091) the Sichuan Province Youth Science and Technology Innovation Team (2017TD0006) 

主　　题：liquid crystalline polymer crosslinking shape memory photo-response self healing 

摘      要：Combining the stability of chemical crosslinking and the processability of physical crosslinking is a well-established strategy to design new materials with desirable stimuli–responsive properties. Herein, a series of azobenzenebased thermotropic liquid crystalline polyesters were synthesized by introducing mesogenic dial named 4,4＇-bis（6-hydroxyhexyloxy）azobenzene（BHHAB）, 2-phenylsuccinic acid（PSA）, and different contents of 1,2,3-propanetricarboxylic acid（PTA） as the chemical crosslinker. All these polyesters showed good thermal stability and smectic liquid crystalline phase. Wide-angel X-ray diffraction（WAXD） and the fluorescence emission spectra confirmed the existence of π–πstacking interactions as the physical crosslinking in the polymer chains, particularly at the lower content of PTA. However, when the PTA content increased, the chemical crosslinking changed the chain conformation, and thus the intensity of physical crosslinking slackened gradually. Combining the physical and chemical crosslinking, these polyesters showed the thermoplastic processability, thermal shape memory, heat-assisted healing and photoresponsive behaviors. Taking advantages of these features, these multiple stimuli–responsive polymers can bring more chances for smart materials such as soft actuator.