Synthesized 20 nm cobalt ferrite single crystals, which exhibited a coercivity of 2.9kOe at room-temperature, were dispersed in precursor polyamic acid at different volume fractions and cured at 300oC to develop the polyimide matrix. Polyamic acid was previously treated with isopropyl thrisostearyl titanate) to improve the dispersion of inorganic particles within the polymer matrix. Solvent-cast free standing films were deposited onto glass substrates. FTIR analyses of the bare polymer and the magnetic nanocomposites verified the formation of the polyimide matrix. XRD analyses of the matrix, disperse phase and nanocomposite also verified the formation of the expected structures. M-H measurements of the corresponding isolated ferrite nanoparticles and the nanocomposite confirmed the tuning on magnetic properties by controlling the volumetric load of the disperse phase. The saturation magnetization of the nanocomposite varied from 13 emu/g up to 25 emu/g when the ferrite volumetric load was increased from 10 to 30% while the coercivity remained unchanged. The dependence of the properties in the nanocomposite, including surface roughness and morphology analyses by AFM, with the functional properties of the disperse phase will also be presented and discussed.
Journal: TechConnect Briefs
Volume: 1, Nanotechnology 2009: Fabrication, Particles, Characterization, MEMS, Electronics and Photonics
Published: May 3, 2009
Pages: 170 - 173
Industry sector: Advanced Materials & Manufacturing
Topic: Nanoparticle Synthesis & Applications