Processing and reprocessing liquid crystal elastomer actuators

Liquid crystal elastomers (LCEs) have long been celebrated for their exceptional shape actuation and mechanical properties. For much of the last half century, a major focus for the field has been the development of LCE chemistries and how to process the so-called “monodomain” configurations. This foundation work has now led to a plethora of materials and processes that are enabling the demonstration of devices that are close to real-world applicability as responsive and reprocessable actuators. In this Perspective, we review and discuss the key recent developments in the processing of actuating LCE devices. We consider how processing has been used to increase the practicality of electrical, thermal, and photo stimulation of LCE shape actuation; how dynamic chemistries are enhancing the functionality and sustainability of LCE devices; and how new additive manufacturing technologies are overcoming the processing barriers that once confined LCE actuators to thin film devices. In our outlook, we consider all these factors together and discuss what developments over the coming years will finally lead to the realization of commercial shape actuating LCE technologies.

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