Conjugated polymers are attractive novel materials whose properties may be tunable after their primary synthesis, by changing their redox state along with their charge while concomitantly dedoping/redoping with appropriate counterions. They can also be made into conductive "synthetic metals" that can be incorporated into electronic circuitry in place of traditional conductors and semiconductors, besides serving as active sensing elements. Their use in sensors is already a maturing field of research, while the perspective of using them in gas separation and pervaporation applications is beginning to emerge. Permeation properties of membranes can be controlled by medium energy (up to a few hundred keV) ion beam irradiation. We present a systematic mathematical modeling approach to describing medium energy (up to a few hundred kcV) ion beam irradiation, which allows to predict implantation and damage depths in any given polymer, for any ions with arbitrarily chosen atomic number and energy. (C) 2006 Elsevier B.V. All rights reserved.