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

). Molecular dynamics simulations reveal that modifications in the number and nature of hydrogen bonds lead to a distinct elastic-plastic transition in hydrogels. Furthermore, the conductive PCTA hydrogel exhibits multimodal sensing capabilities including stretchable strain sensing with a wide sensing range (1-200%), fast response time (180 ms), and excellent linearity of the output signal. Moreover, it demonstrates exceptional temperature and humidity sensing capabilities with high detection accuracy. The strong actuation power and real-time sensory feedback from the composite hydrogels are expected to inspire novel flexible driving materials and intelligent sensing systems.