Preparation of antibacterial polymer-grafted silica nanoparticle and surface properties of composites filled with the silica (2)

Abstract

Antibacterial polymer was grafted onto silica nanoparticle and the surface properties of various composites filled with the silica were investigated. The grafting of antibacterial polymer, poly(vinylbenzyltributylphosphonium chloride) (poly(St-CH2P+(Bu)3Cl)-), onto silica surface was achieved by two methods: one is treatment of poly(vinylbenzylchloride) (poly(St-CH2Cl))-grafted silica with tributylphosphine and the other is direct grafting of poly(St-CH 2P+(Bu)3Cl-) by radical graft polymerization of the corresponding monomer. The grafting of poly(St-CH 2Cl) and poly(St-CH2 P+(Bu)3Cl -) onto silica surface were initiated by the system consisting of trichloroacetyl groups on the silica surface and Mo(CO)6. Trichloroacetyl groups were introduced onto the silica surface by the reaction of amino groups on the silica surface with trichloroacetyl isocyanate. The percentage of poly(St-CH2Cl) grafting during the graft polymerization initiated by the system increased with progress of the polymerization reached 116%. The grafting of poly(St-CH2P+(Bu)3Cl -) onto silica surfaces was confirmed by FT-IR spectra, thermal decomposition gas chromatograms and mass spectra (GC-MS), and l3C-CP/MAS NMR. The surfaces of silicone rubber, polystyrene film, and paints filled with the poly(St-2P+(Bu) 3Cl-)-grafted silica shows strong antibacterial activity. These composites retained the antibacterial activity even after the boiling in water for 24h. © 2009 The Society of Polymer Science, Japan.