Conducting Fabric-reinforced Polyaniline Film Using p-Chlorophenol as Secondary Dopant for the Control of Electromagnetic Radiations

Abstract

Polyaniline (PAn) is a commercially viable conducting polymer exhibiting enough metallic conductivity to replace carbon/metal filled composites as a shield to control electromagnetic radiations. In this paper, we discuss the process to achieve a pore-free conducting fabric reinforced with PAn. The process involves the pretreatment of glass fabric before the in situ polymerization of aniline in the presence of either p-toluenesulfonic acid (PTSA) or camphor-10-sulfonic acid (CSA). The conducting E-glass fabric is coated with a conductive paste prepared from PAn-PTSA or PAn-CSA/p-chlorophenol (PCP) as the secondary dopant come solvent at 60 C to achieve a pore-free flexible conducting surface. The reinforced conducting fabrics are characterized by UV-Vis spectroscopy, conductivity, scanning electron microscopy (SEM), X-ray diffraction study (XRD), and thermogravimetric analysis (TGA). The electromagnetic interference shielding effectiveness (EMI SE) studies are carried out using the co-axial transmission line method in the frequency range of 0.1-1000 MHz. The pore-free conducting fabric reinforced with PAn-PTSA/PCP and PAn-CSA/PCP of 3 mm thickness offered an EMI SE of 58 and 55 dB at 1000 MHz. The study indicates that the SE increases with the increase in thickness and conductivity of the test coupon.

Keywords

conducting glass fabric secondary dopant electromagnetic radiation noncorrosive environmental stability

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