具有核壳结构磁性复合微球的制备与表征  

PREPARATION AND CHARACTERIZATION OF MAGNETIC COMPOSITE MICROSPHERES WITH CORE-SHELL STRUCTURE

作　　者：龚涛[1] 汪长春[1] 

机构地区：[1]聚合物分子工程教育部重点实验室复旦大学高分子科学系,上海200433

出　　处：《高分子学报》2008年第11期1037-1042,共6页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号20674009;20728404);国家杰出青年基金(基金号50525310);教育部培育基金(基金号707023)资助项目;上海市重点学科建设项目资助(项目号B113)

摘　　要：采用两步法制备了具有核壳结构的Fe3O4/P（MMA/DVB）（core）-P（St/GMA/DVB）（shell）磁性复合微球.首先,用改进的细乳液聚合制备了Fe3O4/P（MMA/DVB）微球;然后,加入总量不同的苯乙烯（St）、甲基丙烯酸缩水甘油酯（GMA）和二乙烯基苯（DVB）,通过种子乳液聚合,制备了不同磁含量的核壳结构的磁性复合微球.分别用X-射线衍射（XRD）、高倍透射电镜（HR-TEM）、热重分析（TGA）、振动样品磁力计（VSM）等手段对磁性微球的性能进行了表征.实验结果表明,Fe3O4/P（MMA/DVB）微球的磁含量为84 wt%;通过改变加入壳层单体的量,核壳复合微球的磁含量可控在20 wt%-76 wt%之间.该微球具有超顺磁性,相应的饱和磁化强度为12-50Am^2/kg.Magnetic Fe3O4/P（MMA/DVB）（core）-P（St/GMA/DVB）（shell） composite microspheres with core-shell structure were prepared by a two-step method.（1） Preparation of the magnetic cores：First,the magnetic miniemulsion composed of organic ferrofluid droplets dispersed in water was obtained by rapid addition of an oil-based magnetite ferrofluid,with a solid content 60 wt%,into the aqueous solution using DNS-86（polymerizable surfactant） as surfactant in the condition of ultrasonic emulsification.Then,the copolymerization monomers of methyl mathacrylate（MMA） and divinyl benzene（DVB） were injected directly into the magnetic miniemulsion.Because of their hydrophobic character,once the monomers were added into the emulsion,the methyl mathacrylate（MMA） and divinyl benzene（DVB） would have a high tendency to diffuse inside the organic phase of the ferrofluid droplets to form monomer swelling magnetic miniemulsion,which were supposed to be the main locus for copolymerization.In succession,the temperature was rapidly increased to 70℃ and starting the miniemulsion copolymerization to form uniform magnetic latexes.（2） Preparation of the core/shell hybrid polymeric microspheres：Through varying the feeding amount of styrene（St）,glycidyl methacrylate（GMA） and DVB,the core-shell structured microspheres were rationally fabricated by the seed emulsion copolymerization using the above magnetic latex as the core emulsion.This preparation process is convenient and effective.Extensive characterization by X-ray diffraction（XRD）,high resolution transmission electron microscopy（HR-TEM）,thermogravimetric analysis（TGA） and vibrating sample magnetometer（VSM） showed that the magnetite content of Fe3O4/P（MMA/DVB） composite microspheres was 84 wt%.The magnetite content of the magnetic composite microspheres with core-shell structure is varied from 20 wt% to 76 wt% by feeding different amounts of monomers.The average diameter of the magnetic seeded microspheres and the core-shell

关 键 词：磁性微球 细乳液 核壳结构 超顺磁性 FE3O4纳米粒子 

分 类 号：O631.5[理学—高分子化学]