Microwave Synthesis of Fe 3 O 4 /Poly(styrene- co- acrylic acid) Microspheres with a Narrow Size Distribution

Magnetite microspheres have wide applications in industry and biomedicine. The control of the particle size and size distribution is critical in accurately controlling the chemical and physical properties of the magnetic nanoparticles. Here an efficient microwave-controlled synthesis of Fe 3 O 4 /P(St-AA) microspheres was reported. We found that the reaction rate was accelerated and the size distribution was narrowed with the microwave-assisted synthesis. The size of the microspheres can be controlled by the feeding concentration of the sodium dodecyl benzene sulfonate surfactant with diameters ranging from 200~400 nm. Meanwhile, the magnetic microspheres exhibit superparamagnetic properties with no hysteresis at the low applied magnetic field, which is important for their application in magnetic field-driven applications.