Synthesis And Antibacterial Study Of Novel Polymer

This dissertation consists of five parts:1. ReviewThe chapter describes the classified of antimicrobial agents, compared with their antibacterial mechanism, the advantages and disadvantages. The natural organic antibacterial agents of chitosan and its modified methods, the antibacterial group introducted methods of organic polymer antibacterial agents, and antimicrobial polymer materials was predicted to explain the study antimicrobial polymer materials the background and significance. Make sure the object of composed polymers.2. Study On Synthesis of Amphiphilic Copolymers Containing QuaternaryAmmonium and Its Properties For Antimicrobial Activity A series of novel antimicrobial copolymers were synthesized through the reactive monomers of glycidyl methacrylate(GMA) and vinyl acetate(VAc). By modified research of the poly (GMA-co-VAc), a different proportion of quaternary ammonium polymer could be got. The synthesized quaternary ammonium polymers were characterized by infrared spectroscopy and elemental microanalyses. The antimicrobial activity of the quaternary ammonium polymers were studied through investigation the diameters of the inhibition zones, the minimum inhibitory concentrations, hemolytic, and the effects of the different concentration, time, temperature on the growth of four colonies.The result showed that the quaternary ammonium polymers of GMA:VAc=1:1 had the best antimicrobial activity. The minimum inhibitory concentration of the copolymer against (Candida albicans) was found to be 30.5μg·mL-1, the diameters of the inhibition zones was 6 mm, and also these polymers did not have any hemolytic to mammalian erythrocyte.3. Synthesis and characterization of antimicrobial materials by modified Starch in situ copolymerizationGrafting guanidine polymer (PHGH) onto Starch was conducted by free-radical polymerization using ceric ammonium nitrate (CAN) as an initiator in the acetic acid solution under nitrogen atmosphere and the antibacterial material which had better antibacterial activity was produced. The minimalinhibitory concentration (MIC), inhibition zone and hemolysis of Candida albicans, Staphylococcus aureus, Bacillus subtilis and Escherichia coli were focused on. Meanwhile, the antibacterial activity of the material through the time and temperature on the growth of four colonies were investigated. The findings indicated that the antibacterial activity of new substance was best especially for Candida albicans and had no harm to animals'red blood cells.4. Modification of chitosan and its study of antibacterialGrafting guanidine polymer (PHGH) onto chitosan (CS) was conducted by free-radical polymerization using ceric ammonium nitrate as an initiator in the acetic acid solution under nitrogen atmosphere and the CS/PHGH of new material was produced. The FT-IR, element analysis of new material was tested. And the antibacterial of the new material was investigated. The result showed that the antibacterial activity of CS/PHGH was better than that of CS for fungus, gram-positive bacteria and gram-negative bacteria, especially for fungus. The minimal inhibitory concentration (MIC) was 0.39 mg·mL-1 for fungus, the diameter of the inhibition zones was 21 mm.5. Preparation of novel chitosan by the atom transfer radical polymerization and study on the Antibacterial ActivityThe macroinitiator(CS-Br) was composed with chitosan(CS) and 2-bromopropionyl bromide. Then, with CS-Br as macroinitiator and CuBr/ N,N,N′,N′,N〃-pentamethyldiethylenetriamine(PMDETA) as a catalyst, a novel material P(CS-Br-DMC)was successfully prepared with CS-Br and chlorine methylation dimethyl ammonium ethyl methacrylate(DMC) via atom transfer radical polymerization (ATRP). The minimal inhibitory concentration (MIC), inhibition zone and hemolysis of Candida albicans, Staphylococcus aureus and Escherichia coli were focused on. Meanwhile, the antibacterial activity of the material through the different time on the growth of three colonies were investigated. Furthermore, its water soluble and MIC was compared with CS. The findings indicated that the water soluble and antibacterial activity of new substance was better than that of CS especially for Staphylococcus aureus.