Synthesis of polyaniline/zinc-cobalt ferrite nanocomposites and their use in the preparation of radar absorber coatings

In this research, first Zinc- Cobalt ferrite particles, with Co0.5Zn0.5Fe2O4 formula, was prepared via sol–gel auto-combustion method. The magnetic particles were characterized by WAXD and FT- IR techniques. WAXD analysis exhibited the diffraction peaks of the cubic spinel structure for the synthesized nanoparticles. Then, they were employed in the preparation of PANI/ Co0.5Zn0.5Fe2O4 composites, with 3:1, 1:1 and 1:6 weight ratios, by in situ polymerization of aniline monomer in the presence of proper amount of Co0.5Zn0.5Fe2O4 nano particles and ammonium persulfate as initiator. The synthesized composites were analyzed by FT-IR, SEM and XRD methods. Subsequently, polyaniline/Co0.5Zn0.5Fe2O4 particles were incorporated (in 20 wt. %) in an epoxy resin matrix to produce final nanocomposites. The morphological properties of these composites were investigated by TEM. Based on TEM image, particle sizes between 10-100 nm were found for polyaniline/Co0.5Zn0.5Fe2O4 nano powders. The reflection loss of fabricated nano composites was measured in the radar region, i.e. the frequency range of 8-12 GHz. In the proper amount of 1:1 weight ratio of polyaniline to Co0.5Zn0.5Fe2O4, reflection loss reached its minimum value of -16 dB