Thermal stability of conductive polyaniline-nylon 6 composite fabrics doped by a mixture of protonic acids

We have studied the thermal stability of conductive polyaniline (PANI)-nylo n 6 composite fabrics doped by a mixture of hydrochloric acid (HCl) and var ious organic aryl sulfonic acids such as benzenesulfonic acid (BSA), dodecy lbenzenesulfonic acid (DBSA), and rho -toluenesulfonic acid (TSA). Conducti ve fabrics are prepared by immersing the nylon 6 fabrics in an aqueous hydr ochloride solution of 0.5M aniline and by initiating successive polymerizat ion with an oxidant in various doping solutions. When the same molar ratio of HCl in the diffusion bath and various protonic acids in the polymerizati on bath are mixed and serve as the dopant for polyaniline, the highest fabr ic conductivity is obtained with HCl/BSA, and HCl/TSA, HCl/DBSA, and HCl/HC l in decreasing order. The conductivity of all doped PANI-nylon 6 composite fabrics decays at elevated temperatures in air. Among the various dopants, HCl/DBSA shows the best thermal stability, followed by HCl/TSA > HCl/BSA > HCl in decreasing order.