A class of bioinspired, cross linking polymers, created by working catechol functionalities into the backbone of a bulk polymer, is disclosed. Varied cross linking groups may be incorporated into different polymer backbones, and subsequently reacted with an array of reagents. An adhesive composition comprising a copolymer, the copolymer comprising pendant dihydroxyphenyl groups; and a crosslinking agent selected from the group consisting of, for example, oxidants, enzymes, metals, and light. A method of preparing an adhesive composition comprising copolymerizing a first monomer comprising pendant dihydroxy-protected dihydroxyphenyl groups; deprotecting the dihydroxy-protected dihydroxyphenyl groups; crosslinking the dihydroxyphenyl groups with a crosslinking agent.