Studies of radiolytic processes in siloxane polymers using ESR spectrometry

Full text: Radioluminescent sources based on tritium labeled polymers represent a modern technological variant with applications in defense industry and nanotechnologies. Obtaining radioluminescent sources with high luminances requires identification of synthesis methods of labeled polymers with superior specific activities and use of high raw radioactive materials. Radioluminescent sources, which contain as exciting agents tritium labeled ethyl-siloxane polymers, represent one of the most studied constructive variants. High specific activities needed, induce significant autoradiolytic processes in labeled polymers. Their study is necessary for technological, radiobiological and radioecological reasons. ESR study was performed for the identification of free radicals resulting from the primary radiolytic act in irradiated siliconic polymers. The study was carried out on irradiated dimethyl, ethyl, phenyl and ethyl-phenyl siloxanic structures and the measurements were done at 77 K. Results were inter-compared with the literature results and with those obtained by quantum-mechanical simulation and from radiometric studies on tritium labeled polymers. (author)