Bioinspired Mechanically Responsive Hydrogel upon Redox Mediated by Dynamic Coordination between Telluroether and Platinum Ions

Inspired by natural lives, materials with switchable mechanical properties have been constructed by virtue of the development of dynamic chemistry. However, the limited dynamic reactions are hampering their further development. The progress in organotellurium chemistry brings opportunity to open new frontiers of dynamic reactions for fabrication of mechanically responsive materials. Herein, a bioinspired mechanically responsive hydrogel upon redox mediated by dynamic coordination between telluroether and platinum ions is reported. The low electronegativity and superior σ electron-donating capability of telluroether facilitate its coordination with Pt ions. Remarkably, the coordination interaction is highly redox-active. Telluroether can dissociate from Pt ions upon oxidation (e.g., H₂O₂) because the effect of the polar solvent dramatically reduces the thermodynamic activity of oxidized telluroether. In turn, the coordination interaction is easily regenerated via reduction (e.g., vitamin C) of oxidized telluroether. When the coordination system is introduced into the polymer network of a hydrogel via copolymerization of telluroether containing a monomer and N-hydroxyethylacrylamide, the hydrogel exhibits a switchable and regulatable microporous structure and mechanical strength upon redox stimuli by virtue of the dynamic coordination interaction between telluroether and Pt ions. This work provides a new set of dynamic coordination chemistry and a new strategy to prepare mechanically responsive hydrogel.