Facile synthesis of high-magnetization Fe3O4@polydivinylbenzene core-shell submicrospheres

Fe3O4@polydivinylbenzene (PDVB) submicrospheres were prepared via distillation-precipitation polymerization of DVB in the presence of submicron magnetite colloid nanocrystal clusters (MCNCs) as seeds. The surface of the MCNCs was modified with vinyl groups before PDVB encapsulation. The resulting Fe3O4@PDVB particles showed a well-defined core-shell structure, and the shell thickness could be readily controlled by the DVB dosage. A lowly cross-linked poly(methacrylic acid) (PMAA) layer could be further coated onto the highly cross-linked PDVB shell via a second-stage DPP process, suggesting the presence of residual vinyl groups on the surface of the Fe3O4@PDVB particles. The hybrid particles showed rather high magnetization and near superparamagnetism, hence capable of easy magnetic separation.