Di-2-ethylhexylsulfosuccinate sodium salt(AOT) doped conducting polyaniline (PANI-AOT) was chemically polymerized. It was dissolved into a weakly polar solvent (toluene) and secondary doped with m-cresl. The conductivity of PANI-AOT was sharply increased form 30S/cm to 400S/cm after the secondary doping. Then the conducting polymer was firstly blended with a typical thermoplastic polymer
poly(styrene-co-maleic anhydride) (SMA) by soluon blending method. The conductivity of PANI-AOT/SMA was relatively maintained even at 200℃ for several minutes. The TGA analysis also indicated that the thermostabilities of the blends were obviously improved compared with those of PANI-AOT.