| Polymer/nanoparticles become very active domain at present, displaying good exploitation and application foreground, But because of inorganic particles' smaller dimension, bigger specific surface area, higher interfacial energy, they are prone to agglomerate, and consequently cannot exert nanometric effect to full extent, thus lowering the interfacial energy of nanoparticles, weakening interfacial polarity of nanoparticles and improving compatibility between nanoparticles and polymer, become the most important technological problems for composite materials.In this paper, we select nanometer titanium powder as initiative material, use the coupler WD-70 to modify nanoparticles, graft the long chain of polystyrene onto the surface of nanoparticles by the copolymeriztion between styrene and ethenyl of WD-70. Then the modified nanoparticles are dispersed in the styrene, the composite particles are obtained by miniemulsion polymerization of styrene.In our work, the organic-inorganic composite particles which consist of an inorganic core surrounded by a polymer shell were also successfully prepared by dispersion polymerization of styrene. The nanometer titanium dioxide particles were modified with coupling agent WD-70 and dispersed in the medium applying the ultra-sonic technique and then encapsulated by dispersion polymerization of styrene. The inorganic particles were entirely contained in the polystyrene micro-spheres as evidenced by TEM. It is shown that some polystyrene chains are chemically bonded to the nanometer titanium dioxide particles through the coupling agent WD-70 as evidenced by FTIR, XPS .Monodipersion polystyrene microspheres are prepared through the dispersion polymerization. The effects of media, the concentration of monomer and dispersion stabilizer and initiator on the particles size have been studied. The preparation of colloid crystals is investigated by the self-organization of polystyrene microspheres.
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