Pickering emulsion polymerized smart magnetic poly(methyl methacrylate)/Fe2O3 composite particles and their stimulus-response†
Abstract
Smart polymer/inorganic composite magnetic particles were synthesized by Pickering emulsion polymerization using magnetic iron oxide (Fe2O3) particles as a solid stabilizer. The products were characterized by scanning electron microscopy and transmission electron microscopy, which revealed submicron-sized spherical PMMA covered with Fe2O3 nanoparticles. The thermal properties of the pristine Fe2O3 and PMMA/Fe2O3 composite particles were examined by thermogravimetric analysis. Fourier transform infrared spectroscopy was used to characterize the chemical structure of the samples. The magnetic properties of the products were observed by vibrating sample magnetometry. The rheology of the magnetorheological (MR) fluid of the PMMA/Fe2O3 particles dispersed in a non-magnetic medium fluid was examined using a rotational parallel disk rheometer under an applied magnetic field. Despite the lower magnetic properties compared to those of pristine Fe2O3, the PMMA/Fe2O3 composite particle based MR fluid showed typical MR characteristics with potential dispersion stability regarding the particle density.