Title: Shape-Switchable Liquid-Crystal Polymer Actuators with Light-Induced Shape Memory Effect

Author: Jinlei Wang, Feng Pan, Xiaojun Liu, Lang Qin*, Yanlei Yu

Journal: ACS Appl. Mater. Interfaces, 2025, 17, 48815−48823

Abstract:

The initial shape of a soft actuator plays a vital role in its functional performance as it dictates the internal stress distribution and deformation pathway during the actuation process. Photodeformable liquid-crystal polymers (LCPs) have demonstrated significant potential in soft actuators due to their fast, localized, precise, and reversible deformation under light irradiation. However, the initial shape of LCP actuators is generally nonswitchable once fabricated, limiting them to a single deformation mode and monofunctionality. Herein, we present a strategy for fabricating shape-switchable LCP actuators by integrating an athermal light-induced shape memory effect (SME) into photodeformable LCP systems. The reversible photodimerization of coumarins introduces an additional crosslinking network that regulates the mobility of molecular chains, enabling LCPs to exhibit a light-induced SME for shape-switching. Moreover, the photothermal effect of disperse red 1 acrylate induces mesogen alignment changes under 470 nm light irradiation, allowing for the independent actuation of each switched shape. Leveraging this unique shape-switching mechanism, we fabricated a soft actuator capable of transforming among multiple motion modes, including rolling, crawling, and gripping, for the first time. This study establishes a novel design paradigm for developing multimorphology and multifunctional soft actuators, advancing the complexity and versatility of LCP-based intelligent systems.

论文链接：https://pubs.acs.org/doi/10.1021/acsami.5c12533

PDF下载：Shape-Switchable Liquid-Crystal Polymer Actuators with Light-Induced Shape Memory Effect.pdf

软体执行器的初始形状对其功能性能至关重要，因为它决定了致动过程中的内部应力分布与变形路径。光致形变液晶聚合物（LCPs）凭借其在光照射下快速、局域、精准且可逆的变形能力，在软体执行器领域展现出巨大潜力。然而，传统LCP执行器的初始形状一旦制备完成便无法切换，导致其仅能实现单一变形模式与单一功能。本文提出了一种通过将无热光诱导形状记忆效应引入光致形变LCP体系，从而构建形状可切换LCP执行器的策略。香豆素分子的可逆光二聚反应引入了一个额外的交联网络，可调控聚合物分子链的迁移率，使LCP具备光诱导形状记忆效应以实现形状切换。此外，分散红1丙烯酸酯的光热效应可在470 nm光照射下诱导基元排列变化，从而实现各种形状切换的独立驱动。基于这一独特的形状切换机制，本文首次制备出能够在滚动、爬行与抓取等多种运动模式间转换的软体执行器。本研究为开发多形态、多功能的软体执行器建立了新的设计范式，提升了基于LCP的智能系统的复杂性与多功能性。