An Amino‐Yne Click Chemistry Approach for Multi‐Responsive Liquid Crystal Elastomer Actuators

Abstract The spontaneous amino‐yne click reaction is introduced for the first time as a fast, efficient, and ambient temperature strategy for preparing multi‐responsive Liquid Crystal Elastomer (LCE) actuators. This synthetic approach relies on the amino‐yne cross‐linking between secondary amines along the main chain of poly(β‐amino ester) liquid crystal oligomers and a dipropiolate‐functionalized cross‐linker, rendering β‐aminoacrylate cross‐linking points. After alignment and locking via dynamic transesterification at 30 °C, the resulting LCE actuators exhibit reversible and reproducible thermal and light‐induced actuation. The generated tension and activation kinetics are easily tunable by adjusting the cross‐linker content. Additionally, leveraging the acid‐triggered reactivity of the network enables it to respond to additional stimuli, including water‐driven actuation. By integrating the capability for dynamic bond exchange, this LCE formulation opens new avenues for designing structures with complex molecular orientation patterns. As a proof of concept, a star‐shaped soft actuator is fabricated, demonstrating diverse programmable actuation modes.