Microwave absorption properties of PANI/CIP/Fe3O4 composites

The PANI/carbonyl iron powders (CIP)/Fe3O4 composite was synthesized by mechanical mixing PANI/CIP composite with PANI/Fe3O4 composite with mass ratio of 7:3. The electromagnetic (EM) properties of these composites were studied at 0.5–18 GHz. Compared with PANI/CIP and PANI/Fe3O4 composites, the PANI/CIP/Fe3O4 composites show enhanced EM wave absorption at high frequency range, and the maximum reflection loss is −48.3 dB at 9.6 GHz with a thickness of 1.76 mm. There is no obvious chemical interaction happened during mixing, which retains the magnetic properties of PANI/CIP and PANI/Fe3O4 components. While the conducting channels of the PANI coatings and the metal–polymer interfaces are partly destroyed, which reduces the permittivity and improves the impedance match, hence results in good EM wave absorption for PANI/CIP/Fe3O4 composite.