| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1441665 | Synthetic Metals | 2012 | 7 Pages |
Polystyrene/polyaniline (PS/PANI) composites were prepared by emulsion polymerization of aniline in a mixture of PS and dichloromethane, at different feeding ratios of aniline to PS. Dodecylbenzenesulfonic acid (DBSA) was used as a dopant during chemical oxidation of aniline. Fourier transform infrared (FTIR) spectroscopy, wide angle X-ray diffraction (WAXD), scanning and transmission electron microscopies (SEM and TEM) were used for structural characterization of the composites. The effect of PANI content on electrical properties of the composites was studied by electrical resistivity and electromagnetic interference (EMI) shielding measurements. Electron microscopy showed that the conductive PANI distributed in the continuous PS matrix, heterogeneously. Electrical conductivity, EMI shielding effectiveness, real permittivity and imaginary permittivity values increased with PANI content. It was found that absorption had more contribution to EMI shielding than reflection. 1.1 mm thick samples of the composites exhibited electrical conductivity up to 10−2 S/cm and electromagnetic interference shielding effectiveness (EMI SE) up to 8 dB, for sample containing ca. 20 wt% PANI.
Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Real and imaginary relative permittivity for PS/PANI of ca. 10 at 20 wt% PANI. ► Showed that contribution of absorption more than reflection for EMI shielding. ► Very low electrical percolation at 0.75 wt% PANI. ► Electrical conductivity up to 10−2 S/cm, EMI SE up to 8 dB (1.1 mm thick sample). ► Critical exponent of t ∼ 3 indicating three-dimensional network had formed.
