Core–shell polymerization for monodispersed hollow polymer spheres embedded with magnetic nanoparticles

Monodispersed hollow polymers embedded with Fe3O4 nanoparticles were prepared by core–shell polymerization applied to both the hydrophobic surface and hydrophilic surface of the magnetic nanoparticles. The void size and polymer shell thickness of these hollow polymers can be easily tuned over a wide range. The final magnetic hollow polymers were characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), thermogravimetric analysis (TGA) and magnetic force microscopy (MFM) and confirmed to form capsules embedded with magnetic nanoparticles. These magnetic hollow polymers were stably dispersed in an aqueous phase and were intrinsically superparamagnetic because of the presence of magnetic nanoparticles.