Instant tough adhesion of polymer networks.

Generating strong rapid adhesion between hydrogels has the potential to advance the capabilities of modern medicine and surgery. Current hydrogel adhesion technologies rely primarily on liquid-based diffusion mechanisms and the formation of covalent bonds, requiring prolonged time to generate adhesion. Here, we present a simple and versatile strategy using dry chitosan polymer films to generate instant adhesion between hydrogel-hydrogel and hydrogel-elastomer surfaces. Using this approach we can achieve extremely high adhesive energies (>3,000 J/m ² ), which are governed by pH change and non-covalent interactions including H-bonding, Van der Waals forces, and bridging polymer entanglement. Potential examples of biomedical applications are presented, including local tissue cooling, vascular sealing, prevention of surgical adhesions, and prevention of hydrogel dehydration. We expect these findings and the simplicity of this approach to have broad implications for adhesion strategies and hydrogel design.
Competing Interests: Competing interests statement:J.A.C.C., M.L., D.K., K.C.W., H.M.J., and J.C.W. declare no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. B.R.F. has the following interests: Amend Surgical, licensed IP; Limax Biosciences, equity. D.J.M. has the following interests: Lyell, equity; Attivare, equity; IVIVA Medical, consulting and equity; J&J, consulting; Boston Scientific, consulting; Limax Biosciences, equity; Epoulosis, equity; Revela, equity; Amend Surgical and Sirenex, licensed IP. P.K. has the following interests: Limax Biosciences.