Mussel‐Inspired Hydrogel Composite with Multi‐Stimuli Responsive Behavior

A mussel‐inspired adhesive hydrogel with pH, temperature, and near‐infrared (NIR) light–responsive behavior is designed. The hydrogel system is formulated by combining chitosan modified with catechol motifs, thermo‐responsive poly( N ‐isopropylacrylamide) terminated with catechols, and light‐absorbing polypyrrole nanoparticles (PpyNPs). The effects of catechol concentration, molar ratio of Fe 3+ to catechol units, pH, and the incorporation of...