Measurement and Evaluation of Dielectric, Magnetic and Microwave Absorbing Properties of Carbonyl Iron Loaded Polymer Composites

Composites with carbonyl iron (CI) as filler and polyvinylchloride (PVC) as polymer matrix were prepared and measured in the 1 MHz–3 GHz frequency range to study their dielectric, magnetic and microwave absorbing characteristics. Complex (relative) permittivity ε== ε’ - jε “was mainly caused by the interfacial polarization mechanism. Complex (relative) permeability µ = µ’ - µ” showed a relaxation type offrequency dispersion, which is due to the natural ferromagnetic resonance phenomenon. The ε and ε raised, and the minimum of return loss (RL)min shifted towards low frequencies with increasing CI content. The results outlined that the fabricated composites may be used to design good and cost-effective electromagnetic interference noise suppressors.