A self-healing artificial muscle was realized by fitting the electrode membrane with the self-healing actuating membrane with a folded structure

Abstract

As a part of biomimetic gelatinous polymer actuator (BGPA), hydrogel artificial muscle has the advantages of extreme flexibility, low driving voltage and controllable driving direction. However, such artificial muscles do not have self-healing properties and it is difficult to continue using them if they break, which considerably reduces their lifespan. In this paper, we propose a hydrogel artificial muscle with self-healing capability by gluing a membrane of electrodes with a pleated structure to a self-healing actuator layer. The crosslinking reaction between polyacrylic acid molecular chains and carboxylated chitosan (CLC) molecular chains was utilized to fabricat e self-healing actuator layers, while multi-walled carbon nanotubes and chitosan were employed for electrode films. The impact of CLC doping content on the self-healing properties, mechanical properties, electrical response output force properties, and electrochemical properties of self-healing artificial muscles was investigated. Experimental results demonstrated that the output force density of the self-healing artificial muscle could reach 14.7 mN g−1 with an addition of 0.2 g CLC; even after fracture-self-healing, the maximum output force density of the artificial muscle still remained above 90%, and the maximum stretching stress of the actuator film maintained a range from 91% to 99%, showcasing exceptional self-healing performance.