Trapping of Xenon Induced in Polymeric Films by UV and X-ray Irradiation

X-ray and UV photons were used to store xenon atoms in polymeric films. The trapping was found to be stable at room temperature for Kapton and PVDC films. In Kapton, concentrations of xenon up to about 18.5 mg/cm3 were attained. The dependence of the rare gas concentration on the irradiation dose, film thickness, gas pressure, and on the polymers and gases nature was probed. The results are interpreted in terms of a simple three-step model: the xenon atoms are first physisorbed at the surface of the substrate and then diffuse into the bulk where they are finally trapped as a result of radiation chemistry effects of the UV or X-rays on the structure of the polymer.