Conductive polyaniline (PANI) was prepared by emulsion polymerization with ammonium persulfate (APS) and sodium hypochlorite (NaClO) as composite oxidant. Whether add the NaClO or not, the morphology and electrochemical properties (cyclic voltammogram and electrical conductivity) of PANI were discussed. Moreover, the effect of the concentrations of APS, sodium dodecylbenzenesulfonate (SDBS) and NaClO on electrochemical properties of PANI was discussed. The experimental results showed that NaClO had an important effect on the morphology of PANI. Compared with the PANI synthesized by APS alone, the PANI synthesized by APS and NaClO composite oxidant has higher redox peak current and higher conductivity (which is about 2.6 times the former). The optimal properties of PANI was achieved when the molar ratio of aniline (An) to APS was 8:7, the molar ratio of An to SDBS was 10:4 and Na- ClO was 5% (w). UV-Vis and FT-IR indicated that the structure of PANI synthesized by composite oxidant was similar to the PANI synthesized by APS alone.

Key words: polyaniline, emulsion method, composite oxidant, electrochemical properties