Compositions for use as a tissue glue or sealant are disclosed. The compositions include first and second precursor molecules, wherein the first precursor molecule is a polyoxyethylene-polyoxypropylene block copolymer having at least two nucleophilic groups and the second precursor molecule is a polyoxyethylene-polyoxypropylene block copolymer having at least two electrophilic groups. Biomaterials for use as a tissue glue or sealant, methods of making such biomaterials, devices for applying a biomaterial to a tissue of a patient, methods of sealing a tissue of a patient, and kits also are disclosed.
