Mr Qi LI's paper appears in Extreme Mechanics Letters

2021-02-01

Qi Li, a PhD Student in Dr. Hong’s group published a paper, “Switchable adhesion between hydrogels by wrinkling”, on Extreme Mechanics Letters in January 2021. Other collaborators include Ping Zhang, a Ph.D. student in the department, Prof. Canhui Yang, and Prof. Huiling Duan from Peking University.

This work reports a novel approach for switchable adhesion between hydrogels by invoking a mechanical instability, wrinkling. On one hand, the formation of wrinkles enhances adhesion by creating a tortuous path for crack propagation and an extended energy dissipation zone. The resulting adhesion is robust to elicit bulk dissipation within the adherend and transform the once adhesive failure to cohesive failure. On the other hand, the suppression of wrinkles deactivates the adhesion enhancement mechanism to facilitate effortless debonding. As a proof-of-concept, a hydrogel patch that can strongly adhere to a damaged hydrogel device for repair and gently detach after repairing, based on the switchable hydrogel adhesion, is demonstrated. The proposed method expands the design space for hydrogel adhesion.