Synthesis, characterization, and electrical properties of nanostructural polyaniline doped with novel sulfonic acids (4‐{n‐[4‐(4‐nitrophenylazo)phenyloxy]alkyl}aminobenzene sulfonic acid)

Abstract 4‐{ n ‐[4‐(4‐Nitrophenylazo)phenyloxy]alkyl}aminobenzene sulfonic acid (C n ‐ABSA, where n = 2, 4, 6, 8, or 10) as a novel dopant for conducting polymers of polyaniline (PANI) was designed and synthesized. The molecular structure of C n ‐ABSA was characterized with 1 H NMR, Fourier transform infrared, and secondary‐ion mass spectrometry. Nanostructures (nanotubes or nanorods) of PANI–(C n ‐ABSA) were successfully synthesized with a self‐assembly process in the presence of C n ‐ABSA as the dopant. The morphology (shape and size) and conductivity of the resulting nanostructures strongly depended on the number of alkyl groups ( n ) and, in particular, the addition of water before polymerization. The formed micelles of aniline/C n ‐ABSA/water were proposed to be templatelike in forming PANI–(C n ‐ABSA) nanostructures on the basis of the emulsion properties measured by dynamic light scattering.