Visible Light-Responsive Covalent Adaptable Liquid Crystal Elastomers Enabled by Dynamic Allyl Selenide Bonds
Sisi Chen, Mengyao Zhang, Qingyuan Li, Jiachen Li, Shengpeng Wu, Jian Zhou, Guoqing Jin, Zhengbiao Zhang, Xiangqiang Pan, Jian Zhu
Abstract
Liquid crystal elastomers (LCEs) are excellent polymer materials for a wide range of applications, including soft actuators and shape memory materials. At present, some dynamic covalent bonds (DCBs) have been introduced into LCEs to achieve reprogrammability. However, the contradiction between reprogrammability and stable actuation performance is still a challenge. One of the solutions is to introduce photoactivated DCBs into thermotropic LCEs to maintain their thermal adaptability. Therefore, it is meaningful to find a DCB with thermal stability and mild photoresponse for application in thermotropic LCEs. Herein, we adopt dynamic chemistry of allyl selenide, which not only achieves the separation of network reconfiguration conditions (light) from LC phase transition conditions (heat) but also achieves multiple network reconfiguration of LCEs under visible light conditions (405–450 nm). This dynamic covalent chemistry with mild stimulation conditions and sustainable dynamic exchange capability offers great possibilities for the application and design of covalently adaptable LCEs.