Preparation and magnetic properties of PMMA-encapsulated Fe₃O₄ fine particles

Abstract

PMMA microspheres a few tens micrometer in diameter, in which magnetite (Fe3O4) fine particles were highly dispersed, were prepared by emulsion polymerization method. Octadecyltriethoxysilane acted as an effective surface modifying agent of Fe3O4 for the high dispersion of the Fe3O4 particles in MMA monomer. The magnitude of saturation magnetization was correlated to the Fe3O4 filling fraction of the obtained composite. This method may be expected to be used for preparing a material on a local hyperthermia therapy of deep-seeded cancers when external magnetic field is applied to this material from outside of our body.