Conductivity Enhancement of Polyaniline Through Chemical Oxidative Polymerization Assisted By Strong Acid Dopants
Synthesis of a conductive polymer with enhanced electrical conductivity obtained through chemical oxidative polymerization in is discussed in this paper. The electrical conductive property of polyaniline being a valuable result which is required in various applications.The conversion of aniline monomer into polymer chains was carried out through chemical oxidative polymerization in acidic condition.Water soluble initiator (ammonium persulphate) was used at room temperature (28˚C) for8 hours yielded a conductive polyaniline (PANi). The complete reaction was indicated by a temperature increased up to 33�C at 240 and 270 minutes. It was followed by an increase in the viscosity value of polymer solution to 1.87 mPa.s subject to Ostwald viscometer method. Particle sizesof polymer which are evaluated by Particle Size Analyzer (PSA) indicated that there was a growing in size ofpolymerparticle during the polymerization reactionto a mean size value of approximately 55 �m after the propagation process of carbon chain was ended after 270 minutes reaction time. The conductivity value of PANiemeraldine salt (PANi-ES) was in the range between 8200 �S/cm and 8600 �S/cm. Various strong acids, of respectively Nitric acid (HNO3), Formic acid (HCOOH), Hydrochloric acid (HCl) and Perchloric acid (HClO4) were used as doping agents to enhance the electrical conductivity of PANi-ES. Among the four mentioned doping agents, only HClO4able to enhance the electrical conductivity of PANi-ES. The HClO4 doped PANi-ES resulted in an electrical conductivity value of 27000 - 33104.41 �S/cm subject to evaluation by LCR Meter at frequencies in the range between 0 and 100 KHz. The electrical conductivity of doped PANi at a frequency of 100 kHz is almost 5 times higher than that of obtaining in PANi-ES.
Indexterms- Polyaniline; Strong acid doping agent; Conductive Polymer; Electrical conductivity