A transparent, tough self-healing hydrogel based on a dual physically and chemically triple crosslinked network

Self-healing hydrogels are a new type of functional material that have been widely used in many fields. Although various self-healing hydrogels have been reported, the simultaneous achievement of transparency, toughness, good recovery, and superior self-healing properties is still challenging. Here, we designed a new hydrogel with a dual physical and chemical triple crosslinked network. The triple crosslinked network hydrogel after freeze-thaw cycling exhibited higher stability, toughness and better tensile properties than those provided by the dual crosslinked network in the as-prepared hydrogel. In addition, the triple crosslinked network structure provided reliable recovery performance and superior self-healing ability without requiring external stimuli. With the combination of high transparency, toughness, good recovery, and self-healing properties, we demonstrated the applicability of the hydrogel in resistance and capacitance sensors, which can be applied to a wide range of human motion monitoring and intelligent wearable devices.