Nanocomposites comprised of homogeneously dispersed magnetic iron-oxide nanoparticles and poly(methyl methacrylate)

Nanocomposites with a high, uniform loading of magnetic nanoparticles are very desirable for applications such as electromagnetic shielding and cancer treatment based on magnetically induced hyperthermia. In this study, a simple and scalable route for preparing nanocomposites with a high, uniform loading of magnetic nanoparticles is presented. The magnetic iron-oxide nanoparticles were functionalized with a methacrylate-based monomer that copolymerized in a toluene solution with the methyl methacrylate (MMA) monomer. The resulting suspension of magnetic nanoparticles decorated with poly(methyl methacrylate) (PMMA) chains in toluene were colloidal, even in the presence of a magnetic field gradient. Nanocomposites were precipitated from these suspensions. The transmission electron microscopy investigation of the prepared nanocomposites revealed that the magnetic nanoparticles were homogeneously dispersed in the PMMA matrix, even in amounts up to 53 wt %. The uniform dispersion of the nanoparticles in the PMMA matrix was attributed to the good solvation of the grafted PMMA chains from the magnetic nanoparticles by the PMMA chains of the matrix. The nanocomposites were superparamagnetic and exhibited large values for the saturation magnetization of up to 36 emu/g. Moreover, the nanocomposite with the largest amount of incorporated nanoparticles exhibited relatively large values for the specific power loss when subjected to alternating magnetic fields, giving this material great potential for the magnetically induced hyperthermia-based treatment of cancer.