1,1-二苯基乙烯存在下无皂乳液聚合制备磁性复合微球

报道了一种制备磁性复合微球的方法——DPE法.在自由基控制剂1,1-二苯基乙烯(DPE)存在条件下,甲基丙烯酸甲酯(MMA)与丙烯酸(AA)发生无皂乳液聚合,制备能与Fe3O4粒子相螯合的活性短链共聚物,加入Fe3O4粒子把短链共聚物引到其表面,引发其它单体继续在Fe3O4粒子表面聚合,制备磁性复合微球.研究了AA、DPE、引发剂及Fe3O4粒子加入量等对制备磁性复合微球的影响.并在此基础上,对优化后工艺制备的磁性复合微球进行了TEM、TGA及磁响应性表征.结果表明,利用该新的方法制备出了磁含量为20%、比饱和磁化强度为32.2emu/g、平均粒径为265nm且表面不含任何杂质的磁性复合微球.

PREPARATION OF MAGNETIC COMPOSITE MICROSHERES BY SOAP-FREE EMULSION POLYMERIZATION IN THE PRESENCE OF 1,1-DIPHENYLETHENE

The magnetic composite microspheres,which had no surface active agents on the surface and were more suitable for use of biomedicine,were prepared by a simple method——DPE method. In the preparation of 1,1-diphenylethene ( DPE ),methyl methacrylate ( MMA ) and acrylic acid ( AA ) took place soap-free polymerization,and the living short copolymer chains,which could chelate with Fe3O4,were prepared. Then Fe3O4were added,the living short copolymer chains were chelated to the surface of Fe3O4. The subsequent polymerization could take place on the surface of the Fe3O4,then the magnetic composite microspheres were prepared. The effects of AA,DPE,Fe3O4 and initiator were investigated in detail. With the increase of AA,DPE and initiator,the morphology of magnetic composite microspheres improved and then declined. The morphology of magnetic composite microspheres had no big change with addition of Fe3O4,but the magnetic content increased obviously. The magnetic composite microspheres,prepared in optimum conditions,were characterized by transmission electronic microscopy ( TEM ),thermogravimetric analysis ( TGA ) and vibrating sample magnetometer (VSM). The results showed that for these magnetic composite microspheres the magnetic content was about 20% ,the specific saturation magnetization was about 32. 2 emu /g,the average size was 265 nm and there were no any impurity on their surface.