A novel method for preparation of polymer-based magnetic microspheres was proposed by utilizing melt reactive blending,which was based on selective location of Fe_3O_4 nanoparticles in PA6 domains of polystyrene(PS)/polyamide 6 (PA6) immiscible blends.The morphology of PA6/Fe_3O_4 composite magnetic microspheres was studied by scanning electronic microscopy(SEM).The composite magnetic microspheres were spherical with a diameter range of 0.5-8μm;the diameter was sharply decreased with a very narrow distribution by adding terminal maleic anhydride functionalized polystyrenes(FPS) for reactive blending.Transmission electron microscopy(TEM) and thermogravimetry analysis(TGA) results showed that most of Fe_3O_4 was located in the PA6 microspheres.Magnetization data revealed the magnetite content of PA6/Fe_3O_4 microspheres was about 32 wt%and the saturation magnetization could be up to 17.2 Am^2/kg.
