Stability of biomimetic ferrofluids established by a systematic study using microwave irradiation at defined wattages

Abstract

An established biomimetic process for the synthesis of aqueous ferrofluids using polymers has been subjected to systematic microwave irradiation at different wattages primarily to see if the magnetization could be increased by microwave irradiation and if so how would it affect the stability of the fluid. Care has been taken to maintain ambient conditions of synthesis even after three cycles of microwave irradiation before oxidation and ten cycles after it, so as not to violate the basic principles of the process. Detailed characterization using, x-ray diffractometry, transmission electron microscopy, fourier transform infra-red spectroscopy, dynamic light scattering, thermo-gravimetric analysis, differential thermal analysis and vibrating sample magnetometry showed that these fluids containing iron oxide nanoparticles-poly(vinyl) alcohol nanocomposites are highly stable in the proportions established by us. Measurements at five different wattages double the saturation magnetization but the stability remains unaffected compared to the one without microwave irradiation, forcing us to believe that the incubation of the iron salt solution and the polymer in the right proportion before oxidation is what contributes to the stability and that increasing the number of cycles of microwave irradiation at this stage, perhaps, would have led to a more pronounced effect.