Self‐Healing Metallo‐Supramolecular Hydrogel Based on Specific Ni<sup>2+</sup> Coordination Interactions of Poly(ethylene glycol) with Bistriazole Pyridine Ligands in the Main Chain
Xiaowen Xu, Valentin Victor Jerca, Richard Hoogenboom
Abstract
Abstract In this study, a supramolecular hydrogel formed by incorporating the 2,6‐bis(1,2,3‐triazol‐4‐yl)‐pyridine (btp) ligand in the backbone of a polymer prepared by copper(I)‐catalyzed alkyne‐azide cycloaddition (CuAAC) “click” polyaddition reaction of 2,6‐diethynylpyridine and diazido‐poly(ethylene glycol) is reported. The hydrogelation is selectively triggered by the addition of Ni 2+ ions to aqueous copolymer solutions. The gelation and rheological properties could be tuned by the change of metal to ligand ratio and polymer concentration. Interestingly, the hydrogel exhibits a fast (within 2 min) and excellent repeatable autonomic healing capacity without external stimuli. This self‐healing behavior may find potential applications for the repairing of metal coatings, in the future.