4-Methyltriphenylamine was oxidatively polymerized in chloroform (CL) or propylene carbonate (PC) in the presence of ferric chloride (FeCl3) at 50 degrees C. Polymerization proceeded more rapidly and the molecular weight of the resulting polymer was higher in CL than in PC due to the higher oxidation potential of the solution. The linear structure was confirmed by C-13 NMR, and the resulting polymer exhibited high thermal stability and electrochemical activity.