Title: Multiple Shape Manipulation of Liquid Crystal Polymers Containing Diels-Alder Network

Author: Xin Huang, Lang Qin, Jinlei Wang, Xiao Zhang, Bo Peng, Yanlei Yu*

Journal: Adv. Funct. Mater., 2022, 32(51), 2208312

Abstract:

Multiple shape manipulation of soft materials, including reversible deformation, shape memory effect, and shape remolding, are highly desirable in morphing structures and soft actuators. Although liquid crystal network (LCN) is a promising candidate for realizing anisotropic reversible deformation, developing LCN with multiple shape manipulation remains a multitude of challenges, which is limited to the regulation of mesogens alignment and network topological rearrangement. Here, multiple shape manipulation is demonstrated by a newly designed LCN containing azobenzene moieties and a dynamic Diels-Alder (DA) network. Photodeformation of the LCN is attributed to the ordered lamellar structure of mesogens formed by annealing-induced self-assembly. Light-induced shape memory effect leads to reprogrammable shape changes due to the light-switchable glass transition temperature of the azobenzene-containing LCN. Moreover, the dynamic equilibrium of the DA network endows the LCN with liquid state remoldability and solid state plasticity, which further contributes to diverse 3D geometric shapes in shape remolding. Such LCN exhibiting flexible deformation and remolding properties provides a new photoresponsive block for the fabrication of soft actuators.

论文链接：https://onlinelibrary.wiley.com/doi/10.1002/adfm.202208312

PDF下载：Multiple Shape Manipulation of Liquid Crystal Polymers Containing Diels-Alder Network.pdf

本工作中，我们制备了一种新型含动态Diels-Alder（D-A）交联网络的偶氮苯液晶聚合物(AZO-DAN)，其中偶氮苯基团作为光开关不仅能够控制液晶排列的变化，也能够可逆调控聚合物的玻璃化转变温度在室温上下发生转变，使得液晶分子即具有光致形变能力也具有光致形状记忆效应；此外，D-A动态网络赋予了材料具有溶液重塑和固态重塑能力。这种偶氮苯液晶聚合物有望制备复杂形状的全光控执行器，拓展液晶聚合物的形变方式以及在软体机器人等领域中的应用。