Novel oxidants for polymerization and crystallization of aniline



By using novel oxidants, namely, sodium salt of para-toluene sulfonic acid, lithium perchlorate, and potassium ferricyanide, and varying the oxidant to monomer ratio from as low as 1/100 to 1/20 in the presence of concentrated HCl, it has been possible to simultaneously polymerize aniline and crystallize the polyaniline at room temperature. The crystals thus obtained have been characterized using FTIR, GPC, XRD, and Optical Microscope. It was found that highly crystalline substituted oligo-polyanilines were obtained. The studies indicate that the use of even weaker oxidants, like pTS-Na, LiClO4, and K3[Fe(CN)6], can bring about simultaneous polymerization and crystallization of aniline, as we observed earlier using ammonium persulphate. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 640–646, 2005