Preparation And Characterization Of Silver Iodide Nanoparticle/Polymer Antibacterial Composites, Grafted With Perfluoropolyether Chain

Because of the excellent property, such as low surface free energy, splendid optical properties, electrical properties, thermal stability and chemical resistance, fluoropolymers are potentially useful chemicals in the field of fabric finishing, fiber-coating, microelectronics, and antifouling agent and so on.According to statistics of the WHO, infectious disease caused by the spread and reproduction of bacteria has become one of the main reasons which result in death currently. Because of the excellent property of the organofluorine finishing agent, it became to be the most widely used finish for water-and oil-proofing. So it would well meet the needs of the people if we can endow the hydro-oleophobic organofluorine finishing agent with antibacterial property. However, large numbers of investigation reports show that this type of finish usually containing long perfluoroalkyl chains(-CnF2n+1, n≥8) which can easily accumulate in nature environment without biodegradation and are toxic to human beings. For these reason, it is significant to find an ideal novel non-toxic biodegradable and environmental benign antibacterial material with great hydro-oleophobic property.Based on the quaternization of the pyridine, we synthesized a polymer-base pyridinium iodide (PFPVP) from poly(4-vinylpyridine) and a perfluoropolyether iodide. The iodide anions associated with the amphiphilic pyridinium polymer PFPVP were precipitated by the addition of a silver salt (AgPTS). The resulting silver iodide nanoparticles are stabilized by the steric effect of the polymer. Thus a highly potent dual action antibacterial composite (Agl/PFPVP) consisting of a cationic polymer matrix and embedded silver iodide nanoparticles was fabricated. The perfluoropolyether chain endows the composite with excellent hydro-oleophobic property, and which is easier to undergo biodegradation than perfluoroalkyl chains does at the same time. NMR, FT-IR, EDS, et al were used to characterize the AgI/PFPVP. The thermal stabilities of the polymers were analysed by TG analyses. The glass coated with these polymers possessed excellent hydro-oleophobic property. The water contact angle could be achieved from119degree to141degree. Oleophobicity grade can reach level7. The synthesized composites have potent antibacterial activity toward both gram-positive and gram-negative bacteria, proved to have broad-spectrum antibacterial ability. We also demonstrate the abilty to tune the antibacterial activity of the composite by controlling the size of the embedded Agl nanoparticles through the feeding ratio of perfluoropolyether iodide and silver salt.