Biocompatibility,particularly blood compatibility is the most important property required for biomedical materials.The improvement of blood compatibility is always an important research task for biomaterial research and development.It is an important way to develop biomaterials by constructing special molecules onto the proper mechanical material surface.Polyetherurethanes are widely used as biomaterials due to their good biocompatibility and mechanical properties.Nevertheless,their blood compatibility is still not adequate for the more demanding applications.The purpose of present study was to synthesis a novel nonthrombogenic biomaterial by modifying the surface of polyetherurethane.Ozone was used to introduce active peroxide groups onto polyetherurethane surface and graft polymerization of N,N dimethyl N methacryloxyethyl N (3 sulfopropyl) ammonium (DMMSA), a sulfobetaine structure,onto the ozone activated polyetherurethane surface was conducted.The nonthrombogenic properties of grafted film were also studied.The grafted film was characterized by ATR FTIR,XPS and contact angle measurement.The ATR FTIR,XPS of the grafted PU film indicated that the graft polymerization did take place,the grafted PU film surface was covered with the DMMSA polymer.The grafting yields in different condition were studied.The grafting yields increased with the increase of the monomer concentration.Water absorption and contact angle showed that the hydrophilicity of the film had been improved greatly,and the hydrophilicity of the film increased with the grafting yield.The blood compatibility of the grafted films was evaluated by platelet adhesion in platelet rich plasma and scanning electron microscopy observation using PU film as the reference.No platelet adhesion was observed for the grafted films incubated for 60 min and 180 min,however,the ungrafted PU film was covered with platelet.The result of platelet adhesion experiment indicated that the PDMMSA chains could prevent platelet adhesion.That means this new material is expected t
