原位聚合制备PLLA/Fe_3O_4磁性复合微球及其表征

Preparation and Characterization of PLLA/Fe_3O_4 by Surface Initiated Ring-Opening Insitu Polymerization

介绍了一种新的PLLA/Fe3O4磁性复合微球的制备方法——表面引发开环聚合法,先利用硅烷偶联剂Z-6040对Fe3O4进行改性,在其表面引入羟基,再通过羟基引发丙交酯在磁粒子表面开环聚合制备PLLA/Fe3O4磁性复合微球。探讨了复合微球的形成机理,对磁粒子改性效果和微球形貌、粒径、结构、磁含量及磁性能等进行了表征,并详细研究了磁性复合微球性能的影响因素。

A novel method for preparing composite microspheres formed by a Fe3O4 nucleus and a grafted Poly（Llactide） （PLLA） shell was introduced. Hydroxyl groups were introduced on the Fe3O4 nanoparticles surface by grafting of Z-6040 to initiate the ring-opening polymerization of L-lactide in the presence of stannous oetoate （Sn （Oct）2）. PLLA chains were directly connected onto Fe3O4 surface through a chemical linkage. The properties of the surface-modified Fe3O4 and subsequent mierospheres were measured separately. The factors that affected the size and Fe3O4 content of PLLA/Fe3O4 mierospheres were also investigated.