Energetic distribution of the electrons from a 200 keV beam in polyurethane layers: EGS4 calculation and FTIR analysis

The aim of this study is to characterize the chemical transformation of a p olymer resulting from irradiation by a 200 keV electron beam. Thermoplastic PU polyetherurethane material was used and irradiation was performed with applied electron fluences in the range of 10(14)-10(17) electron cm(-2) at 77 K. The chemical changes have been observed by FTIR analysis of irradiated laye rs. A NH bond evolution study has allowed us to follow polymer degradation versus depth and fluence. The results have been compared to a simulation of electronic energy loss and to the energy spectrum of the generated electro ns in the polymer using EGS4 code. (C) 2001 Elsevier Science Ltd. All right s reserved.