Flexible and shape-reconfigurable hydrogel interlocking adhesive for high adhesion in wet environments

Abstract

We present wet-responsive, shape-reconfigurable and flexible adhesives that exert strong adhesion under wet environments based on a reversible interlocking between reconfigurable hydrogel microhook arrays. Based on the hydration-triggered shape reconfiguration of the hydrogel microstructures, the adhesions between interlocked microhook arrays were greatly elaborated under wet conditions. Furthermore, the wet adhesion was monotonically increased with water-exposure time. The maximum adhesion force as high as ~79.9 N cm-2 in the shear direction was obtained with the hydrogel microhook array after 20 h swelling. A biomedical bandage utilizing the hydrogel microhooks was proposed as an example of the possible applications.