Conductive Self-Healing Nanocomposite Hydrogel Skin Sensors with Antifreezing and Thermoresponsive Properties

With growing interest in flexible and wearable devices, the demand for nature-inspired soft smart materials, especially intelligent hydrogels with multiple perceptions towards external strain and temperatures to mimic the human skin is on the rise. However, simultaneous achievement of intelligent hydrogels with skin-compatible performances, including good transparency, appropriate mechanical properties, autonomous self-healing ability, multiple mechanical/thermo responsiveness, and retaining flexibility at sub-zero temperatures is still challenging, and thus limits their application as skin-like devices. Here, conductive nanocomposite hydrogels (NC gels) were delicately designed and prepared via gelation of OEGMA-based monomers in glycerol-water co-solvent, where inorganic clay served as physical cross-linker and provided conductive ions. The resultant NC gels exhibited good conductivity (~3.32×10-4 S/cm, akin to biological muscle tissue) and an autonomously self-healing capacity (healing efficiency reach...