Abstract
The work reported here is focusing on the synthesis of the conducting polyaniline (PANI) and its doping with dodecylebenzenesulfonic acid (DBSA) in the presence of oxalic acid. In the first step, polyaniline was synthesized under variable experimental conditions, such as concentration of monomer and reaction time via chemical oxidation polymerization approach. In the second step, PANI was doped with DBSA to enhance its conducting behavior. Both the un-doped and DBSA doped PANI samples was subjected to various characterization techniques. Fourier-transform infrared spectroscopy (FTIR) was used to determine important functional groups and reaction progress, while UV–Vis spectroscopy was used to not only confirm the reaction optimization, but also to trace various characteristic peaks of PANI and its doped version. Both spectroscopic results support the formation and successful doping of PANI. Similarly, X-ray diffraction (XRD) was applied to investigate the nature and phase changes of the synthesized polymer materials. This indicated that the material properties of the samples were affected by varying the composition of reactant moieties. Overall the obtained polymer was amorphous with same crystalline degree. Scanning electron microscopy (SEM) was also employed to investigate the morphology, surface properties and average size of the particles. It was seen that the average size of the polymer chain is in the micrometer range with loose cotton shaped irregular geometry. Further to deduce the thermal stability and phase changes, thermo gravimetric analysis (TGA) was carried out at constant heating rate at different temperatures. This phase changing with changing the temperature suggested the typical polymer/amorphous nature of the synthesized samples. It was also seen that the thermal stability and chain entanglement were affected by changing the chemical composition of samples. The solution conductivity showed that the synthesized samples possess good electrical conductivity with some dependency on the chemical composition.