Nanoclay-based conductive and electromagnetic interference shielding properties of silver-decorated polyaniline and its nanocomposites

Abstract

Polymer composite materials have seen rapid growth in popularity over the past two decades due to their ability to successfully combine the benefits of several different polymer composites into a single product. Conducting polymers (CPs) are more promising materials than other polymers due to their diverse electronic applications, including electromagnetic interference (EMI) shielding, light-emitting diodes, energy storage devices, and the most sophisticated forms of sensors. In this study, the effect of nanoclay on the electrical conductivity, humidity, and EMI shielding properties of silver-decorated polyaniline and its nanocomposites has been investigated. Silver-decorated polyaniline was prepared by using an in situ polymerization technique at 0–5 °C in the presence of ammonium persulphate, which acts as an oxidizing agent. Varied weight% amounts of nano clay were mixed in the conducting silver-decorated polyaniline to obtain their nanocomposite. The synthesized silver-decorated polyaniline and its composites were characterized by using several physical methods, viz., Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD) analysis, and scanning electron microscopy (SEM). All these spectral data reveal the structural characteristics, morphology, and uniform distribution of silver and nano clay particles in the conducting polymer composites. The AC electrical conductivity data show that increasing the nanocrystal weight percentage increases its electrical conductivity. The electromagnetic interference shielding effectiveness of silver-decorated polyaniline nano clay composites shows 90% attenuation between −5 and −8.5 dB. Humidity sensitivity showed a linear relationship with increasing nano clay weight in the decorated polyaniline due to the porosity of the nanoclays and specific adsorption of moisture content. Hence, these composites can be used as a promising material for humid sensors, EMI shielding, battery capacitors, and other technological applications.