Chiral Morphing of Liquid Crystal Polymer Networks

Liquid crystal polymer networks represent a fascinating and promising class of soft materials due to their inherent stimuli-responsive contraction and expansion, the direction of which is determined by the alignment director. This unique feature makes liquid crystal networks a prime candidate for the development of chiral actuators, and this topic has seen a marked increase in interest during recent years. This review brings together the various studies on macroscopic chiral shape morphing in liquid crystal polymer networks and actuators. First, it discusses the theoretical and fundamental studies that demonstrate how the shape selection arises from the anisotropy, geometric misorientation and aspect ratio of liquid crystal polymer ribbons. Then, it summarizes the different ways in which chiral shape morphing can be achieved, including bilayers, mechanical shaping, and 3D printing. Then it gives some examples of the exciting potential applications that have been developed for these systems, including function actuators inspired by plant tendrils and flowers and soft robotics applications.