Bionic energy-storage ejection actuator of electrothermally stimulated liquid crystal elastomer

Liquid crystal elastomers (LCEs) have broad application potential in flexible robots and actuators. However, developing practical flexible actuators with simple sensing capability and self-adhesive properties remains a key challenge in this field. Inspired by the rapid tongue-ejection and capture mechanisms observed in certain animals, an energy-storage ejection actuator based on electrothermal stimulation of LCEs was designed. An amide bond (AM) intermediate was introduced into the liquid crystal polymer to fabricate the AM-LCE film, forming a strong microphase separation structure through hydrogen-bond interactions between the amide groups. This configuration enhanced the breaking tensile strength (5 MPa) and actuating strain (32.8 %) of the LCE film while effectively reducing the isotropic–anisotropic phase transition temperature ( T NI ∼56.5 °C). Based on a strain mismatch strategy, the AM-LCE film, polyimide (PI) heating film and polydimethylsiloxane (PDMS) film were integrated into an energy-storage ejection structure to effectively address the problem of interfacial delamination between layers. The thickness and pre-stretching ratio of the AM-LCE and PDMS films were optimised to enable rapid ejection, grasping, and adhesion at 12 V, with a response time of 1–9 s. This study further broadens the design framework of LCE-based materials and demonstrates their potential applications in bionic ejection actuators.