Thermal Stability of Conductive Polyaniline-Nylon 6 Composite Fabrics Doped by a Mixture of Protonic Acids

Abstract

We have studied the thermal stability of conductive polyaniline (PANI)-nylon 6 composite fabrics doped by a mixture of hydrochloric acid (HCl) and various organic aryl sulfonic acids such as benzenesulfonic acid (BSA), dodecylbenzenesulfonic acid (DBSA), and ρ-toluenesulfonic acid (TSA). Conductive fabrics are prepared by immersing the nylon 6 fabrics in an aqueous hydrochloride solution of 0.5 M aniline and by initiating successive polymerization with an oxidant in various doping solutions. When the same molar ratio of HC1 in the diffusion bath and various protonic acids in the polymerization bath are mixed and serve as the dopant for polyaniline, the highest fabric conductivity is obtained with HC1/BSA, and HC1/TSA, HC1/DBSA, and HC1/HC1 in decreasing order. The conductivity of all doped PANI-nylon 6 composite fabrics decays at elevated temperatures in air. Among the various dopants, HC1/DBSA shows the best thermal stability, followed by HC1/TSA > HC1/BSA > HC1 in decreasing order.