A Highly Stretchable, Tough, Self‐Healing, and Thermoprocessable Polyacrylamide–Chitosan Supramolecular Hydrogel

Polymerization of acrylamide in concentrated aqueous solution in the presence of chitosan and in the absence of covalent cross‐linker leads to the formation of stiff and tough supramolecular polymer hydrogels that are self‐healing, can be stretched up to ≈30 times their original length, and demonstrate rapid self‐recovery, due to the inter‐chain hydrogen bonds between polyacrylamide and chitosan acting as sacrificial bonds to dissipate energy. These gels show thermoplastic behavior and can be molded into different shapes after a heating–cooling cycle, maintaining reasonable mechanical strength. The gels can withstand repeated compressive loading–unloading cycles, exhibiting reliable load‐bearing capacity.