Programming Hydrogen Bonds for Reversible Elastic-Plastic Phase Transition in a Conductive Stretchable Hydrogel Actuator with Rapid Ultra-High-Density Energy Conversion and Multiple Sensory Properties.

Smart hydrogels have recently garnered significant attention in the fields of actuators, human-machine interaction, and soft robotics. However, when constructing large-scale actuated systems, they usually exhibit limited actuation forces (≈2 kPa) and actuation speeds. Drawing inspiration from hairspring energy conversion mechanism, an elasticity-plasticity-controllable composite hydrogel (PCTA) with robust contraction capabilities is developed.