Simple Model of Radial Structure of Latent Tracks in Polymers

Abstract

The radial structure of latent tracks created by energetic heavy ions in polymers is described by a model assuming that the final track structure is determined mainly by chemical reactions of transient degradation products produced during the ion passage. The initial, spatially dependent concentration of the transients is calculated from the local density of the energy dissipated by the secondary electrons. The transients reacting mutually and with the surroundings give rise to two stable products, i.e. low mass fragments and cross-linked structures which, together with intact macromolecules, affect the local properties of the modified material within the track zone. The model describes reasonably the radial structure of the latent tracks, the observed radial dependence of the radial etch rate and relates the measurable data with more fundamental parameters such as transient radiation yield, effective reaction rates and solubility of the three basic constituents.