Synthesis of magnetic microspheres with controllable structure via polymerization-triggered self-positioning of nanocrystals.

A facile and novel method for the synthesis of magnetite-polymer hybrid microspheres with controllable structure is reported. On the basis of the interactions between polymers and magnetic nanocrytals, which are coated with a primary oleic acid layer, a variety of magnetic microspheres with well-tailored structure are fabricated by carefully modulating polymerization and selecting components of composite microspheres; the evolvement of hierarchical structure, and the magnetic properties of microspheres were systematically studied. Importantly, the mechanism of polymerization-triggered self-positioning of magnetic nanocrystals is investigated.