中文摘要：

采用分散聚合法制备出聚（甲基丙烯酸甲酯-co-苯乙烯）种子微球,再将种子微球与甲基三甲氧基硅烷的水解溶液混合,加入氨水使硅烷水解产物在种子微球表面缩聚,制备出聚（甲基丙烯酸甲酯-co-苯乙烯）/聚硅氧烷核壳微球。采用SEM、TEM、粒度分析仪和FTIR对微球的形貌、核壳结构、粒径和化学组成等进行表征。发现在合成种子微球时提高甲基丙烯酸甲酯在共聚单体中的投料比,可使相应核壳微球的折光指数下降。将核壳微球作为光散射剂添加在聚甲基丙烯酸甲酯（PMMA）中制备出光散射材料。结果表明,核壳微球可显著提高PMMA样片的雾度,且PMMA样片的雾度随着核壳微球与PMMA的折光指数之间差值的增加而增加;当核壳微球的添加浓度为2%～3%（质量）时,制得的PMMA样片（2mm）的有效光散射系数均达到55%以上。

英文摘要：

Micron-size poly（methyl methacrylate-co-styrene）/polysiloxane core/shell microspheres were synthesized.Firstly,poly（methyl methacrylate-co-styrene）microspheres were prepared by dispersion copolymerization and acted as seed microspheres.Secondly,methyl trimethoxylsilane was hydrolyzed,mixed with the seed microspheres and then condensed to generate polysiloxane shells on the surface of seed microspheres by adding aqueous NH4OH as catalyst.The morphology,core/shell structure,size and chemical structure of the core/shell microspheres were investigated by SEM,TEM,size analyzer and FTIR,respectively.The refractive indices of the relevant core/shell microspheres decreased with increasing feed amount of methyl methacrylate in the co-monomers in the seeds.The microspheres as light scattering agents were blended with polymethyl methacylate（PMMA）resin to prepare a light scattering material.The results indicated that core/shell microspheres could significantly improve the haze of PMMA sheet（2 mm）and the haze of PMMA sheet was enhanced corresponding to the increase of Δn,the difference of refractive indices between light scattering agents and PMMA.When the concentration of core/shell microspheres was between 2% and 3%（mass）,the light scattering material with effective light scattering coefficient more than 55% could be obtained.