Facile Method for Synthesis of Fe3O4@Polymer Microspheres and Their Application As Magnetic Support for Loading Metal Nanoparticles

A general method was developed for the synthesis of Fe3O4@polymer microspheres with well-defined core-shell structure and various functional groups and strong magnetization through a facile in situ distillation-precipitation polymerization. In this approach, the as-prepared Fe3O4 microspheres were directly coated by a polymer shell through the hydrogen bond interaction between the Fe3O4 micropsheres and oligomer without any surface modification. Moreover, hydrophilic or hydrophobic monomer or even their comonomers with different functional groups such as carboxyl, hydroxyl, amide, and ester were facilely encapsulated onto the surface of the magnetite microspheres. The thickness of the polymer shell layer was tuned by the feed of monomer amount. As for application, Fe3O4@P(MBAAm-co-MAA) microspheres that contained carboxyl groups were used as a magnetic catalyst support to load a series of metallic nanoparticles such as Ag, Pt, and Au. These strong magnetic microspheres were characterized by transmission electron microscopy, X-ray diffraction, Fourier-transform infrared spectra, thermogravimetric analysis, and vibrating sample magnetometry.