High-Performance Organohydrogel Artificial Muscle with Compartmentalized Anisotropic Actuation Under Microdomain Confinement

Adv Mater. 2023 Mar;35(9):e2202193. doi: 10.1002/adma.202202193. Epub 2023 Jan 5.

Abstract

Current hydrogel actuators mostly suffer from weak actuation strength and low responsive speed owing to their solvent diffusion-induced volume change mechanism. Here a skeletal muscle-inspired organohydrogel actuator is reported in which solvents are confined in hydrophobic microdomains. Organohydrogel actuator is driven by compartmentalized directional network deformation instead of volume change, avoiding the limitations that originate from solvent diffusion. Organohydrogel actuator has an actuation frequency of 0.11 Hz, 110 times that of traditional solvent diffusion-driven hydrogel actuators (<10-3 Hz), and can lift more than 85 times their own weight. This design achieves the combination of high responsive speed, high actuation strength, and large material size, proposing a strategy to fabricate hydrogel actuators comparable with skeletal muscle performance.

Keywords: artificial muscle; muscle-mimicking; organohydrogels; phase transitions; soft confinement.