SUPERPARAMAGNETISM OF FERRITE PARTICLES DISPERSED IN SPHERICAL POLYMERIC MATERIALS

Superparamagnetic iron oxide particles synthesized in water-in-oil mic roemulsions have been incorporated into a polymer matrix. The microstr uctured micellar environment provides a template for polymer synthesis , leading to the formation of interconnected polymer particles with sp herical morphologies. The resulting iron oxide-polymer composites reve al superparamagnetic properties and low temperature remanence and susc eptibility characteristic of a superparamagnet. The results of tempera ture and field dependent magnetic characterizations of these composite s are described. Ultramicrotomed TEM micrographs show that the iron ox ide particles (size < 100 Angstrom) are uniformly distributed in the p olymer microspheres.