The electroactivity of electrogenerated polypyrrole films was degraded by applying consecutive anodic potential pulses (overoxidation). After each degradation step, the electroactivity of the material was recorded by voltammetric and chronoamperometric measurements. The charge consumed during each degradation step was calculated by the difference between the degradation and the control chronoamperograms. The diffusion coefficients of the counterions within the material were obtained from the control chronoamperograms by applying the electrochemically stimulated conformational-relaxation model. As the materials became increasingly degraded, slower oxidation processes were observed, and decreasing diffusion coefficients were obtained. These observations point to growing cross linking between neighboring polymeric chains during the degradation process, thus reducing conjugation lengths and increasing the rigidity of the conformational electro-chemo-stimulated movements on the chains. An electroactivity degradation of 50% induces a 15% increase in the weight of the material, pointing to the presence of rigid and oxidized islands entrapped by cross-linking points that prevent any ionic interchanges.