Study On The Property Of Antimicrobial Agent And Antimicrobial Plastics

In this paper, we chose three antimicrobial agents: Ce⁴⁺/ZnO composite antimicrobial agent,Ag-carrying phosphate glass antimicrobial agent and Biofoam liquid antimicrobial agent which was used in the foaming system. The Ce⁴⁺/ZnO composite antimicrobial agent powder was self-prepared by optimization technology. The experiment studied on the antimicrobial activity of the three antimicrobial agents, and we applied them to the polymer to prepare antimicrobial plastics.With nano- ZnO as carrier, the Ce⁴⁺/ZnO composite antimicrobial agent was prepared by the best technology. The influences of different proportion of ZnO and Ce⁴⁺ on doping ratio were investigated. The antimicrobial activity was examined through the experiment of antibacterium-circle and MIC (Minimal inhibitory concentration), and the antibacterial mechanism of the compound antimicrobial agent was also studied. The results showed that the adsorption rate of the nano- ZnO for Ce⁴⁺ was 100%, and the ratio of ZnO to Ce⁴⁺ had little effect. Furthermore, the antimicrobial activity and photocatalytic activity of the nano- ZnO had been evidently improved through doping rare earth cerium. The MIC of Ce⁴⁺/ZnO composite antimicrobial agent against Escherichia. Coli was 100mg/l, and Staphylococcus. Aureus was 150mg/l, it had good antimicrobial effect. We applied it to the polymer with PE as the matrix resin to prepare Ce⁴⁺/ZnO antimicrobial polyethylene plastics by the extrusive technology of melting blend. The results showed that, PE antimicrobial plastics showed high rate of properties to prices by adding 1% antimicrobial agents, and had excellent and long-acting antibacterial activities. Their antibacterial rates were all above 97% against Escherichia.Coli and Staphylococcus. Aureus, also the antibacterial effect against Escherichia.Coli was better than that of Staphylococcus. Aureus.Ag-carrying phosphate glass antimicrobial agent had excellent antimicrobial activity, its MIC against Escherichia. Coli was 50mg/l, and Staphylococcus. Aureus was 100mg/l. We also studied on the properties of antibacterial polypropylene compound material with Ag-carrying phosphate glass antimicrobial agent. The experiment results showed that the antibacterial efficiency of PP was above 99% by adding 2‰antimicrobial agents, and the PP antimicrobial plastic had excellent and long-acting antibacterial activities.We chose three methods to prepare antimicrobial masterbatches: mediate method,single screw extrusive method and twin screw extrusive method. The results showed that the best way was adopted twin screw extrusive method to prepare antimicrobial masterbatches, then applied the antimicrobial masterbatches to polyethylene to prepare antimicrobial plastics. The antimicrobial plastics had the best antimicrobial effect by this way. The method of preparing antibacterial plastic by adding antibacterial masterbatches could bring antimicrobial agent concentrated and symmetrical to the surface of matrix resin, and the mechanical property of matrix resin was not affected.We prepared microcellular foamed antimicrobial polymer with Ag-carrying phosphate glass antimicrobial agent and Biofoam liquid antimicrobial agent which was used in the foaming system. The results showed that the microcellular foamed antimicrobial PP had excellent antibacterial effect and long-acting antibacterial activities. Microcellular foam worked in coordination with antimicrobial effect. Compared the microcellular foamed antimicrobial PP with the foamed PP samples without antimicrobial agent, its Tensile Strength was lower, but the Elongation at Break,Flexure Strength,Impact Strength at room temperature and the Density were higher. Antimicrobial agent had little affected about the foaming rate,cell amounts and the cell distribution. Also Ag-carrying phosphate glass antimicrobial agent had the effect of reducing in the cell size of the foaming system.