Strengthening Actuation of Liquid Crystal Elastomers via Double-Network Construction with Meshed Fabrics

Liquid crystal elastomers (LCEs) have attracted wide interest due to their characteristic large strain in actuation. However, their high transition temperatures to the isotropic phase (<i>T</i>_I) and poor mechanical strength still limit their applications. Here, an LCE network was modified with poly(ethylene glycol) soft segments to lower its <i>T</i>_I, which was adjusted close to body temperature. Additionally, a mesh-structured power-net fabric in a prestretched state was introduced into the LCE matrix to reinforce the soft actuators via construction of a double network. The obtained fabric-reinforced LCE exhibited a high Young's modulus (12.3 MPa, 3 times that of LCE) and an actuation strain of 15%. During one actuation cycle, it experienced a retractive stress of 1.21 MPa, accompanied by a maximum work density of 138 kJ/m³. Both the mechanical and actuation properties of the LCE have been improved. This new strategy of combination brought the LCE actuators closer to practical applications.