EFFECT OF TRANSITIONS ON CONDUCTIVITY OF POLYANILINE SYNTHESIZED USING DIFFERENT DOPANTS BY CHEMICAL OXIDATION

The present work reports the chemical oxidation synthesis of polyaniline using ammonium persulphate (APS) as an oxidizing agent and H2SO4, HCl and CH3COOH as dopants. The samples were characterized by FTIR, UV-Vis, and their conductivity determined by four-point probe method. Quinoid and benzenoid bands at 1553-1596 cm -1 and 1437 – 1496 cm-1 respectively where observed in all the samples. Different transitions present in the bulk samples of PANI were determined by UV-VIS spectroscopy. It was found that the transition π i- iπ* iforiPANI-H2SO4 ioccurs iearlier ithan iin iPANI-HCl isample.iThis ican ionly ibe ias ia iresults iof ithe iH2SO4 iacid ibeen ia istronger iacid ithan ithe iHCl iand ias ia iresults ithe itransition ifrom iπ iiπ* irequired ilower swavelength ifor iPANI-H2SO4 isample ias icompared ito ithe iPANI-HCl isample.iBy icomparing ithe ifour isamples ithe iπ i- iπ* itransition ithen ican ibe iarranged ifrom ithe istrongest ito ithe iweakest ias iPANI-H2SO4 ifollowed iby iPANI-HCl ithen iPANI-HNO3 iand ithe iweakest ibeen iPANI-CH3COOH that also show the trend of observed conductivities in these samples.