Patent ID: 6942822

Claim:
An improved process for the preparation of polyaniline salt by polymerization, the said process comprising steps of: (a) dissolving an anionic surfactant in distilled water and mixing with solution of radical initiator in an organic solvent to obtain a milky white emulsion at a temperature in the range of 30°-50° C., (b) adding drop-wise an aqueous mixture of an aromatic amine and an organic acid to step (a) emulsion, and stirring the above mixture for a period of 4 to 24 hrs at a temperature in the range of 30°-50° C. to obtain a green emulsion, (c) allowing the green emulsion of step (b) to settle and then separating the upper aqueous phase and the lower green oily phase containing the polyaniline salt, (d) washing the green oily phase of step (c) repeatedly with water, diying it over anhydrous sodium sulphate and then filtering it to obtain polyaniline salt in organic solvent, (e) optionally precipitating polyaniline salt by adding the solution of step (d) to acetone or formic acid, and (f) separating the precipitated solid, drying it at about 100° C. to obtain a solid polyaniline salt.