Hydrogen Emission and Macromolecular Radiation-Induced Defects in Polyethylene Irradiated under an Inert Atmosphere: The Role of Energy Transfers toward trans-Vinylene Unsaturations.
This article is aimed at studying the evolution of H2release as well as radiation-induced defects in polyethylene (PE), as a function of the irradiation dose under anoxic conditions. We analyze the influence of the energy transfers and trapping toward radiation-induced defects on the evolution of the radiation chemical yields with dose. One key objective herein is to quantify the contribution of these transfers toward trans-vinylene (TV) on H2emission. For this purpose, pure PE was irradiated in a large dose domain and H2emission was compared to that in predoped PEs containing chemically inserted TV groups irradiated at low doses. In parallel, evolutions of the concentrations of the TV groups and minor defects (vinyl and trans-trans-diene) as a function of dose were considered. Moreover, measuring simultaneously H2and unsaturated groups had allowed inferring the cross-linking evolution with dose. With this methodology, we have succeeded in quantifying the efficiency of TVs and cross-links as energy traps and, using simple models, in fully describing the evolution of all of the radiation chemical yields. Besides, irradiations were performed using either low linear energy transfer irradiations (electron beams, γ rays) or ion beams, with the objective to assess the influence of the high ionization and excitation densities induced by the latter on PE ageing and energy transfer processes.
Centre de Recherche sur les Ions, les Matériaux et la Photonique (CIMAP), UMR 6252, CEA-CNRS, Boulevard Henri Becquerel , BP 5133, 14070 Cedex 5, France.
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Ventura
Centre de Recherche sur les Ions, les Matériaux et la Photonique (CIMAP), UMR 6252, CEA-CNRS, Boulevard Henri Becquerel , BP 5133, 14070 Cedex 5, France.
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Ngono-Ravache
Centre de Recherche sur les Ions, les Matériaux et la Photonique (CIMAP), UMR 6252, CEA-CNRS, Boulevard Henri Becquerel , BP 5133, 14070 Cedex 5, France.
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Marie
Centre de Recherche sur les Ions, les Matériaux et la Photonique (CIMAP), UMR 6252, CEA-CNRS, Boulevard Henri Becquerel , BP 5133, 14070 Cedex 5, France.
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Levavasseur-Marie
Laboratoire de Chimie Moléculaire et Thioorganique (LCMT), UMR 6507 , 6 Boulevard Maréchal Juin, 14000 Caen, France.
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Legay
Laboratoire de Radiolyse et de la Matière Organique (LRMO), CEA Saclay , 91191 Gif-sur-Yvette Cedex, France.
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Dauvois
Univ. Lille, CNRS, ENSCL, Centrale Lille, Univ. Artois, UMR 8181, Unité de Catalyse et de Chimie du Solide (UCCS) , F-59000 Lille, France.
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Chenal
Univ. Lille, CNRS, ENSCL, Centrale Lille, Univ. Artois, UMR 8181, Unité de Catalyse et de Chimie du Solide (UCCS) , F-59000 Lille, France.
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Visseaux
Centre de Recherche sur les Ions, les Matériaux et la Photonique (CIMAP), UMR 6252, CEA-CNRS, Boulevard Henri Becquerel , BP 5133, 14070 Cedex 5, France.
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Balanzat