The influence of PVP on the synthesis and electromagnetic properties of PANI/PVP/CIP composites

Polyaniline/carbonyl iron powder (PANI/CIP) composites with core‐shell structure were synthesized via in situ polymerization in aqueous solution of polyvinylpyrrolidon (PVP). The micromorphology, structure, and microwave absorbing property of the PANI/PVP/CIP composites were characterized by scanning electron microscopy, fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), and vector network analysis. And, the modified mechanism of PVP on polymerization was discussed. The research showed that the presence of PVP was conducive to not only dispersion of CIP but also the formation coated well with PANI. PANI/CIP composites that were decorated by PVP have obviously improved on wave absorbing property compared with the composites which were synthesized without PVP. With the concentrations of 10 wt% PVP, the PANI/PVP/CIP composites show best microwave absorption, which the minimum reflection loss (RL) was −26.4 dB at 38.1 GHz and the corresponding thickness was 0.9 mm; for a thickness of 1.1 mm, an RL exceeding −10 dB was obtained in the frequency range of 27.6–39.0 GHz. POLYM. COMPOS., 36:1799–1806, 2015. © 2014 Society of Plastics Engineers