Synthesis, dielectric and magnetic characteristics of poly(1-vinyl-1,2,4-triazole) (PVTri)-barium hexaferrite composite

The production of PVTri-BaFe12O19 composites was carried out by in situ polymerization of PVTri in the presence of synthesized BaFe12O19 particles. Crystalline phase was determined as BaFe12O19 by XRD analysis and thermal analysis revealed an inorganic content of similar to 45% in the composite. SEM and TEM analyses showed strongly agglomerated particles in the range of 200 nm to several micrometers in the composite. The dielectric function of the various temperatures showed frequency dependency in a reciprocal power law. The dissipation (or loss) of energy stored within the composite was found to obey the reciprocal rule of power law of the frequency dependency. The real part of electrical modulus formalism increased exponentially with frequency for various temperatures, reaching a constant value and finally saturated. The imaginary part showed a reciprocal power law against the applied frequency and shifted to higher frequency at elevated temperatures. Magnetization measurements revealed substantially lower saturation magnetization of the composite material as compared to the bulk barium ferrite powders, possibly due to pinning of some of the surface spins by the adsorption of the PVTri molecules to the surface of the BaFe12O19. (C) 2011 Elsevier B. V. All rights reserved.