The effects of the magnetic field (MF) (0.4 T), the mass ratio of n-butanol (nBA) to composite emulsifier (K_m＝m_nBA/m_SDBS/TX-100) and sodium dodecylbenzenesulfonate (SDBS) to Triton X-100 (TX-100) (S_m＝m_SDBS/m_TX-100) on the phase behavior and conductivity of the microemulsion system during composite emulsifier/aniline polymerization were investigated by the pseudo-ternary phase diagram of SDBS/TX- 100/nBA/An/HCl, which was prepared by using SDBS and TX-100 as composite emulsifier under acidic conditions for the first time. The results showed that with the increase of K_m, the area of microemulsion region increased initially and then decreased, the area reached the maximum on condition that K_m is equal to 1.0|with the decrease of the S_m, the area increased gradually|the area was increased by the MF, and with the decrease of the S_m, the effect of MF on the microemulsion system was weakened. The characterization result of cyclic voltammogram (CV) showed that the CV property of the polyaniline prepared by microemulsion polymerization in the presence of composite emulsifier was better than that prepared in the presence of single emulsifier (SDBS or TX-100).

Key words: aniline, magnetic field, microemulsion, phase behavior, pseudo-ternary phase diagram