| With low density, large surface area and the hollow part which could encapsulate a lot of large molecules, hollow polymer microspheres have great useful in the medical, biochemistry and chemical engineering areas. While ,nano metal particles, because of their excellent and unique property when mixed with other materials, have broad potential application in catalyzer,physic-material, electronmagnetism functional material, sensor material and so on.In this thesis ,we use a method to prepare maleic anhydride-alt-vinyl acetate / maleic anhydride-alt-divinylbenzene core/shell microspheres by "stabilizer-free" dispersion seed polymerization, and then loading nano silver particles in the hollow particles with liquid phase reduction. The nano silver particles could load in the hollow part, while the size and the amount of silver partilces could control by adjust the concentration of AgNO3 solution,dosage,time and other reaction conditions.The hollow microspheres were highly cross-linked with surface reactive anhydride groups. By hydrolysis, the hydrophilic property can be improved significantly ,meanwhile the products with carboxyl on their surface were obtained.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,dosage, recation time on the thickness and morphology of the silver layer was investigated, indicating that the silver particles grew bigger with the increasing of the silver nitrate concentration and reaction time, to 80nm for the most. By electrical conductive testing, the great conductive property of polymer microspheres covered silver layer was proved. while with the lower density compared to the conventional silver material,it was easy to dispersed in various carriers. This organic-meatl composite microspheres have potential application in conductive materials and light weight materials.
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