Inorganic salts effect on the properties of polyaniline

Conducting polymers have been widely investigated for over two decades. Pol yaniline, one of the most stable and processible conducting polymers, was s ynthesized by adding inorganic salt technique. A high molecular weight with lower polydispersity (Mw similar to 200,000 and PD < 2.0) polyaniline was made and characterized by elemental analysis, GPC, FTIR, UV/Vis, and soluti on MMR. It was found that the polyaniline powder morphology such as, partic le size and surface areas, can be controlled by the crystal shapes of inorg anic salts and their concentrations. A "pseudo protonic doping" mechanism i s proposed when adding a high concentration inorganic salts. Certain amount (0.5 similar to3 wt.%) inorganic salts act as "gel-inhibitors" to extend t he gelation time of polyaniline solution and the surface morphologies of po lyaniline film and blends. A high conductivity of the film was obtained and discussed in the paper.