Effect of molecular weight and polymer composition on gallol-functionalized underwater adhesive.

Despite high demands from various industries, strong adhesion in a wet environment remains challenging. We investigated the underwater adhesion of gallol-functionalized polymers as a function of molecular weight and gallol content. By optimizing these parameters, the underwater adhesion strength of aluminium substrates exceeded 4 MPa. Therefore, the biomimetic molecular design of phenolic polymers is effective for the development of strong underwater adhesives.