Mussel-Inspired Self-Adhesive, Antidrying, and Antifreezing Poly(acrylic acid)/Bentonite/Polydopamine Hybrid Glycerol-Hydrogel and the Sensing Application

Hydrogel has great application prospect in the field of flexible wearable devices; however, its poor antifreezing and antidrying properties hinder its applications in wearable devices. Herein, a self- adhesive glycerol- hydrogel (G-hydrogel) with antifreezing and antidrying properties was prepared successfully. The glycerol and water double-solvent system endowed excellent antifreezing and antidrying properties with hydrogel, which ensured the flexibility of the G-hydrogel even after being frozen for 24 h at -15 degrees C or stored at room temperature for a long time. Polydopamine (PDA)-intercalated bentonite (BT) incorporated into the G-hydrogel contributed good comprehensive mechanical property to the G-hydrogel. The peeling test results confirmed that G-hydrogel has good adhesion to natural and synthetic materials because of the existence of PDA with catechol structure. Particularly, the G-hydrogel presented marvelous sensing capabilities for strain and pressure and could monitor the movements of a human. In summary, this kind of self-adhesive, antidrying, and antifreezing hybrid G-hydrogel may be a very promising soft material for flexible wearable devices.