The irradiation-induced grafting of nano-silica with methyl silicone oil

Abstract

To investigate the irradiation-induced grafting of nano-silica with methyl silicone oil, the evolution of irradiation-induced paramagnetic materials in nano-silica was studied. Electron paramagnetic resonance (EPR) characterization shows that nano-silica irradiated in Argon produce relatively stable paramagnetic materials, the quenching rate of which would be accelerated when exposed to air or at elevated temperatures. The addition of irradiated nano-silica into methyl silicone oil in argon significantly increases solution viscosity compared with the non-irradiated controls, suggesting the grafting of silica with silicone oil. The purified products of grafted silica show –CH3 peaks in FT-IR characterization. 1H and 13C NMR characterization are also consistent for the detection of –CH3 in grafted nano-silica. These results confirm that paramagnetic materials in nano-silica can migrate to the surface and graft with polymers. This phenomenon is helpful in understanding the influence of irradiation to interface interaction of nano-silica filled composites, also suggests a novel modification method for inorganic nano-materials.