Magnetopolymer Composites With Soft Magnetic Ferrite Filler

Thanks to their good magnetic properties, NiZn ferrites can be used as the soft magnetic filler in magneto-polymer composites. The ferrites having general composition NixZn_1-xFe₂O₄ ( x=0.30, 0.33, 0.36, 0.42, and 0.50) were prepared by means of ceramic method and the magnetic properties, such as initial permeability μi and Curie temperature TC were investigated. The sample with composition Ni_0.33Zn_0.67Fe₂O₄ having μi=1316 and TC=95°C was chosen as the filler for magneto-polymer composites. The aim of the work was the study of preparation and properties of magnetic polymer composites based on natural rubber SMR 20 in a wide range of concentrations (0-600 phr). The influence of ferrite content on magnetic, physical-mechanical and rheological properties of prepared composites was investigated. The effect of the concentration of ferrite filler on the complex permeability μ = μ^´-jμ^´´ of the composites in the frequency range from 10 MHz to 3 GHz as well as the physical-mechanical and rheological properties is evident.