Chemical synthesis of polypyrrole doped with dodecyl benzene sulfonic acid

Abstract

Among the conducting polymers, polypyrrole (PPY) is one of the most attractive polymer due to its wide range of applications related to its good stability and conductivity. How-ever its insolubility in some common organic solvents limits its wide range of applications. In the present work an attempt has been made to synthesize soluble and stable PPY by inverse emulsion polymerization using dodecyl benzene sulfonic acid (DBSA) as a dopant as well as surfactant. A mixture of chloroform and 2-butanol was used as a novel dispersion medium and benzoyl peroxide as an oxidant. Optimizing the concentration of monomer and oxidant, the percent yield of PPY salts was calculated. Intrinsic viscosity of the PPY salts was calculated using capillary viscometer and was found to be dependent upon monomer concentration. Synthesized PPY salts were characterized by FTIR, XRD, SEM and CV. The thermal stability of the PPY-DBSA was determined by TGA in which a thermogram showing three step decomposition patterns was obtained. The synthesized PPY-DBSA was found to be stable upto 520 ºC, which is so far the highest thermal stability reported for PPY.