| In the present work, cobalt ferrite nanocrystals were synthesized under size-controlled conditions in aqueous phase and incorporated into a polyimide matrix at various volumetric loads. Synthesized 20nm-cobalt ferrite single crystals, which exhibited a coercivity of 2.9kOe at room-temperature, were dispersed in polyimide precursor using two dispersion techniques: (homogenizer and ball mill) and cured to develop the polyimide matrix in the resulting nanocomposites. Produced films were characterized by Fourier transform infrared spectroscopy, X-ray diffraction and vibrating sample magnetometry, which confirmed the formation of the nanocomposite. As expected, the saturation magnetization in the nanocomposites varied according to the Polyimide/Ferrite weight ratio, while coercivity remained at the value corresponding to pure cobalt ferrite nanocrystals. In addition, thermal degradation, thermal stability and dynamic mechanical analyses tests were conducted to assess the viability of the two selected nanocomposites fabrication processes and thus to establish the temperature range in which produced composites can be used. |
