Surface biocompatible modification of polyurethane by entrapment of a macromolecular modifier

► Polyurethane-block-poly(vinylpyrrolidone) (PU-b-PVP) copolymer was synthesized by coupling hydroxyl-terminated PVP with diisocyanate-terminated poly(ethylene glycol) using 1,6-hexamethylene diisocyanate (HDI) as coupling agent. ► The synthesized surface modifier was blended with PU. ► The PU-b-PVP additives could effectively diffuse onto the PU surface to enhance the surface hydrophilicity of PU. ► The blood and cell compatibilities of the PU films were improved by entrapment of a few PU-b-PVP copolymers into PU.