Polyaniline (PAn) doped with dodecyl benzene sulfonic acid (DBSA) was synthesized by emulsion polymerization of aniline under the presence and absence of a constant magnetic field (0.4T).The effects of temperature on the redox (doping-dedoping) behavior of PAn in PAn/m-cresol solutions were systematically investigated by characterization and analysis of FT-IR spectroscopy

conductivity change of the product/m-cresol solution with temperature under the presence and absence of an external electric field

the changes of pH and colors of the solution.The measurement results of the pH and conductivity in the PAn/m-cresol solution showed that the conductivity of the PAn/m-cresol solution was directly proportional to the concentration of the dissociative doping acid getting away from PAn

and the dedoping degree of PAn was enhanced with the temperature increasing and lowered with the temperature decreasing.Moreover

the PAn/m-cresol solution showed obvious abrupt change in its conductivity from the presence of external electric field to its absence at same temperature.Compared with the abrupt conductivity change in the m-cresol solution of PAn synthesized under the absence of magnetic field

the abrupt conductivity change in the m-cresol solution of PAn synthesized under the presence of magnetic field was more remarkable.However

the conductivities of the m-cresol solutions prepared from dedoped PAn were generally low and inert to the changes of temperature and they never underwent abrupt change in their conductivity from the presence of external electric field to its absence at same temperature.It was thought that because under the presence of an external electric field there was an oriented rearrangement of doped PAn in the m-cresol solution

but not for the dedoped PAn.Moreover

not only the oriented rearrangement under external electric field but also the redox behavior of PAn were related to doping level

the greater the doping level

the more remarkable the special behaviors.