Oligomer‐Derived Photoresponsive Liquid Crystal Elastomers with Biocompatible Operating Temperature

Abstract

Abstract Photoresponsive liquid crystal elastomers (LCEs) that can undergo light‐induced actuation at a selected operation temperature range are potent functional materials that can be applied in diverse contexts, including biotechnology and soft robotics. Recent advances in LCE research highlighted the benefits of oligomeric precursors, which enable the use of 3D‐printing, microfluidic or other shear‐based processing to shape and simultaneously program the LCE. The synthesis of photoresponsive nematic LCE sheets derived from oligomers functionalized with azobenzene moieties is reported, followed by a systematic analysis of their actuation as a function of temperature with and without UV light irradiation. By studying the nematic–isotropic transition before and during UV irradiation the optimum photoactuation operating temperature is identified. For the LCEs, this is found to be as low as 30 °C, with near‐identical performance at 37 °C. This renders them ideal for application in biotechnological contexts, hence the new LCEs may enable isothermally operated soft actuators embedded in organoids or living systems. It is discussed how this can be achieved without exposing the cells to harmful UV light.