The charge transfer process in electroactive films involves an insulator/conductor transition produced by the change in the oxidation state of the film matrix. The accumulation of positive (or negative) charges in the films is compensated by cation or (anion) expulsion and/or anion (or cation) incorporation. These processes involve the diffusion/migration of ions and electrons inside the film and the exchange of solvent molecules with the electrolyte. This flow of species is a characteristically non linear, dissipative process which must also be strongly influenced by feedback. Non linearity, dissipation and feedback in a dynamical system are clearly contained in a quadratic logistic equation. Thus, it is of much interest from a conceptual point of view to show that this equation can describe the flow of ions and associated phenomena, like changes in absorbance, in an electroactive film promoted by a potential scan into the active region.