Conducting polymer composites, which are simply physical mixtures of an insulating polymer matrix and intrinsically conducting polymers, are promising new materials for various applications such as antistatic coatings, shielding and electromagnetic absorbers. In this context, a novel conducting composite was successfully produced. It is based on epoxy resin and polyaniline (PANI) doped in benzene sulfonic acid, which was used as conducting filler. The effect of PANI loading levels on the structural, morphological, thermal, electrical and dielectric properties was explored using techniques, such as Raman, Fourier transform infrared and ultraviolet-visible-NIR spectroscopy, X-ray diffraction, atomic force microscopy, scanning electron microscopy, thermogravimetric analysis and differential scanning calorimetry. The electrical behavior and morphology of the synthesized PANI revealed disorder and defects. In addition, as the applied voltage is increased, the current through the sample increases rapidly. The conductivity and dielectric properties were also investigated at room temperature in the frequency range of 1 MHz-1 GHz. The dielectric constant was shown to increase with increased loading at low frequencies and then decreases rapidly, reaching a constant value at higher frequencies. In addition, the AC conductivity of the prepared composites increases with the addition of PANI and is higher at high frequencies. Furthermore, the stability of the composites was found to be influenced by increasing the amount of PANI filler in the matrix.

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We have investigated the possibility of obtaining the conducting form of polyaniline (PANI) using a one-step preparation route. The polyaniline is chemically synthesized in presence of either 1,5-naphtalene disulfonic acid (NDSA) as a dopant or the couple 1,5-naphtalene disulfonic acid as a dopant and the chromotropic salt as a co-dopant (NDSA-Chromo). We present here the study of the spectroscopic, structural and electronic properties of the obtained salts of PANI.During this primary doping of PANI, only a single protonation by NDSA occurred. A co-protonation by HSO 4 − appeared impossible in the presence of an organic disulfonic acid of strong acidity. This conclusion was confirmed not only by the elemental analysis but also by FTIR. The spectroscopic studies (UV-Visible-NIR) showed localization of the charge carriers (polaron) in the synthesized PANI.Using this strategy, we hoped that each NDSA molecule might protonate two PANI amine sites to form a hierarchically ordered supramolecular structure. The obtained compounds show only a limited degree of crystallinity which is however sufficient to propose a possible structural organization. The adjunction of the co-dopant does not modify the local structure of the conducting material and conductivities in the 0.1 S/cm range are obtained for samples with partial doping level.Further improvements in processing can be achieved in particular by using different solvents for obtaining films. In this respect, further progress is possible and this preparation path is worth to be explored in the future.