中文摘要：

采用表面引发原子转移自由基聚合方法合成了核壳结构的磁性高分子纳米微粒．作为聚合反应引发剂的3-氯丙酸，首先与油酸修饰的Fe3O4纳米微粒表面的部分油酸置换，然后在Fe3O4纳米微粒表面引发甲基丙烯酸甲酯聚合，合成的纳米复合材料用TEM，FTIR，XRD和DSC表征．磁性测试结果表明，所制备的磁性高分子纳米微粒仍具有超顺磁性，但由于聚合物的存在，其饱和磁化强度降低．

英文摘要：

This paper described the synthesis of a new Fe3O4/PMMA core-shell nanocomposite particles with magnetism. The modified Fe3O4 nanoparticles were firstly synthesized by ligand exchange with 3-chloropropionic acid as the initiator from oleic acid. And then, PMMA was polymerized by surface-initiated atom transfer radical polymerization （ATRP） on the surface of Fe304 nanoparticles. The nanocomposites were characterized by TEM, FTIR, XRD and DSC. The magnetic properties of the Fe3O4 nanoparticles and the Fe3O4/PMMA nanocomposite were also studied. The saturation magnetization of the nanocomposites was reduceded because of the existence of the polymer.