Xiao Yao-Yu, Jiang Zhi-Chao, Hou Jun-Bo, Zhao Yue
Département de chimie, Université de Sherbrooke, Sherbrooke, QC, J1K 2R1, Canada.
Nat Commun. 2021 Jan 27;12(1):624. doi: 10.1038/s41467-021-20938-6.
Liquid crystalline network (LCN) actuator normally deforms upon thermally or optically induced order-disorder phase transition, switching once between two shapes (shape 1 in LC phase and shape 2 in isotropic state) for each stimulation on/off cycle. Herein, we report an LCN actuator that deforms from shape 1 to shape 2 and then reverses the deformation direction to form shape 3 on heating or under light only, thus completing the shape switch twice for one stimulation on/off cycle. The deformation reversal capability is obtained with a monolithic LCN actuator whose two sides are made to start deforming at different temperatures and exerting different reversible strains, by means of asymmetrical crosslinking and/or asymmetrical stretching. This desynchronized actuation strategy offers possibilities in developing light-fueled LCN soft robots. In particular, the multi-stage bidirectional shape change enables multimodal, light-driven locomotion from the same LCN actuator by simply varying the light on/off times.
液晶网络（LCN）致动器通常会在热诱导或光诱导的有序-无序相变时发生变形，在每个刺激开/关周期内在两种形状之间切换一次（液晶相中的形状1和各向同性状态下的形状2）。在此，我们报道了一种LCN致动器，其仅在加热或光照下从形状1变形为形状2，然后反转变形方向形成形状3，从而在一个刺激开/关周期内完成两次形状切换。通过不对称交联和/或不对称拉伸，在两侧具有不同起始变形温度并施加不同可逆应变的整体式LCN致动器中获得了变形反转能力。这种不同步的驱动策略为开发光驱动的LCN软机器人提供了可能性。特别是，多级双向形状变化能够通过简单地改变光照开/关时间，使同一LCN致动器实现多模态光驱动运动。
