Preparation Of Highly Cross-Linked Polymer Hollow Microspheres With High Mechanical Strength And Their Application In The Adsorption Of Nano Silver Particles On Their Surface

Hollow polymer microspheres have the novel "encapsulate" property because of their low density, large surface area and the hollow part which could encapsulate a lot of large molecules. This property makes hollow polymer microspheres useful in the medical, biochemistry and chemical engineering areas.In this thesis we firstly used a type of novel "stabilizer-free" dispersion polymerization to initiate the seeded polymerization on the surface of maleic anhydride-alt-vinyl acetate polymer microspheres template and obtained maleic anhydride-alt-vinyl acetate / maleic anhydride-alt-divinylbenzene core/shell microspheres. The morphology, polymerization features and kinetics were investigated. It was shown that the reaction reached a high conversion (90%) within quite a short time (10 hours).In addition, we obtained the hollow polymer microspheres with the homogeneous shell and surface reactive anhydride groups by dissolving the template with acetone. It was shown that the shell thickness and the morphology of the hollow polymer microspheres could be adjusted by changing the template concentration, reaction solvents proportion, monomer proportion, solid content, cross-link degree and initiator concentration.The products were highly cross-linked with surface reactive anhydride groups. Making the products hydrolysis can improve hydrophilic property significantly and obtain the products with carboxyl on their surface.Moreover, we prepared the hollow polymer microspheres with the nano silver particles on their surfaces by using the interaction between carboxyl and silver ion. The influence of Silver nitrate concentration and pH vale was investigated. It was shown that the silver particles grew bigger with the increasing of the silver nitrate concentration and pH vale. We applied the microspheres in the antibacterial experiment and found the microspheres excellent antibacterial materials. This type of organic-metal microspheres has excellent bactericidal activity and potential applications as bactericidal agents in biomedical fields.