Underwater Bonding with Charged Polymer Mimics of Marine Mussel Adhesive Proteins

A family of biomimetic copolymers incorporating both 3,4- dihydroxyphenylalanine (DOPA) chemistry and cationic charges was developed to explore the role of charge on adhesion. Four polymers were prepared to investigate the influence of charge upon adhesion, each with the catechol monomer content held constant at approximately 10%. Analogous underwater adhesion experiments were carried out with the aluminum substrates submerged in artificial seawater during both the polymer application and cure at room temperature. The data indicate that the polymers of intermediate charge may be exhibiting greater adhesion. The polymer charge are found to increase the surface wetting of these polymer solutions when underwater. When dry, polymer charge appears to increase the surface wetting of these polymer solutions when underwater.