In the first part of this study, the structtural and thermal characterization of electrochemically and chemically polymerized poly(paraphenylene vinylene), (PPV), have been investigated by direct pyrolysis mass spectrometry. Thermal characteristics, and degradation products of electrochemically prepared poly(paraphenylene vinylene). Pyrolysis study indicated that thermal decomposition of PPV occurs at least two steps. The first being due to the loss of supporting electrolyte present and the second being decomposition of the polymer backbone.In the second part of the study, direct insertion probe pyrolysis mass spectrometry (DIP-MS) technique was used to perform the thermal and the structural characterization of electrochemically synthesized polyaniline,PANI. The effect of dopant used (HCL, HNO3 and H2SO4) and synthesis period have been investigated. For all the samples studied, three main thermall degradation stages have been recorded / evolution of low molecular weight species, evolution of dopant based products and evolution of degradation products of polymer.