Modificated Polyurethane With Zwitterionic Diblock Copolymer For Characterization

Zwitterionic polymers have anion and cation groups simultaneously,which make them forming hydration layer on the surface.Such hydrated layer,based on the electrostatic interaction,effectively resist nonspecific protein adsorption and render zwitterionic polymers excellent biocompatibility.Therefore,zwitterionic polymers have great potential for the anti-biofouling solutions.As one of the representatives,the sulfobetaine polymers,possessing strong hydration and ultra-low biofouling performance,as well as low cost and other advantages,has become the one of the hotspots in the research seeking anti-biofouling solutions.In this paper,four different segment copolymers synthesis with methacryloxyethyl sulfobetaine and 2-hydroxyethyl acrylate(PSBMA-b-PHEMA)using copper bromide(CuBr)/bi-pyridine(BPY)catalytic system,2-bromoisobutyramido ethyl(EBIB)as the initiator via atom transfer radical polymerization(ATRP)methods.Copolymers structures have been identified by nuclear magnetic resonance spectrometer(1H-NMR)and gel permeation chromatography(GPC),which results indicated the successful synthesis of block copolymers.Novel zwitterionic waterborne polyurethane was prepared with improved anti-fouling properties,after the copolymers mixed with polyurethane emulsion by reactions between hydroxyl groups in the copolymer chains and isocyanate groups in polyurethane.Water contact angle(SCA),the equilibrium water content(EWC),infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS)measurement confirmed the existence of zwitterionic polymer in polyurethane and showed improved water affinity of the modified membranes.Protein adsorption measurement and bacterial-adhesion test indicated excellent resistance to biofouling adsorption.P(60-b-30)modified polyurethane exhibited the best performance to suppress most of the protein adsorption and bacterial adhesion among the series.Comparing with amount of unmodified sample,BSA adsorption on modified ones was reduced to 58.3%,fibrinogen adsorption was reduced to 22.4%.,and Staphylococcus aureus adsorption was reduced to 35.4%.The techniques to modify polyurethane with SBMA copolymers as provided herein,have the following advantages:(1)Successful synthesis of block copolymers with methacryloxyethyl sulfobetaine and 2-hydroxyethyl acrylate(PSBMA-b-PHEMA)using atom transfer radical polymerization(ATRP)for the first time.(2)Successfully modified polyurethane with zwitterionic copolymer of enriched hydroxy by mixing copolymer PSBMA-b-PHEMA with the polyurethane emulsion,heating dehydration,deblocking isocyanate,to form a crosslinked interpenetrating network,for the first time.(3)Surface-grafting shows antimicrobial activity in short time.Its antibacterial properties waning as the aging of the surface of polyurethane.In this paper,zwitterionic copolymer was modified into the polyurethane,to form a crosslinked network structure,which can render polyurethane long-term antimicrobial activity.(4)Anti-fouling performance of polyurethane was significantly improved with a simple modification process,providing a feasible and effective method for its applications in the medical field.