PSI - Issue 20

Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000 – 000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000 – 000

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ScienceDirect

Procedia Structural Integrity 20 (2019) 75–80

1st International Conference on Integrity and Lifetime in Extreme Environment (ILEE-2019) Investigation of the climate resistance of stabilized polyethylene composite materials Petukhova E. S.* and Fedorov A.L. Institute of Oil and Gas Problems of the Siberian Branch of the RAS - Division of Federal Research Centre “The Yakut Scientific Centre of the Siberian Branch of the Russian Academy of Sciences”, Avtodorozhnaya str. 20, Ya kutsk, 677007, Russia Abstract The article presents the studies of the climate resistance of polyethylene composites containing different stabilizers. To carry out complex climatic studies, we chose materials with the highest and most stable mechanical characteristics and density. It has been found that the use of sulfur-containing stabilizing additives leads to a color change of the samples after 1 month of exposure, probably due to the formation of quinone during decomposition of stabilizing additives. It is shown that one of the most sensitive indicators of polyethylene aging is elongation at rupture. The study of the dependence of elongation at rupture on the period of exposure in the open air showed that the use of stabilizers of grades СО3 and СО 4 in an amount of 0.3-0.5 wt.% is sufficient to maintain stable work of products and constructions for 1 year. Whereas the original polyethylene and the composite containing Stafen stabilizer become embrittled after 9 months of exposure. The electron microscopic studies have shown that the submolecular structure of the composites significantly depends on the exposure conditions. The most prominent changes in the structural characteristics were found for the composites exposed in the open air. Significant temperature drops during the test period cause these changes. In the general case, it has been found that the use of stabilizers of grades СО3 and СО4 can extend the service life of products and constructions of unpainted polyethylene in the climatic conditions of the Sakha Republic (Yakutia) by 25% (from 9 to 12 months). 1st International Conference on Integrity and Lifetime in Extreme Environment (ILEE-2019) Investigation of the climate resistance of stabilized polyethylene composite materials Petukhova E. S.* and Fedorov A.L. Institute of Oil and Gas Problems of the Siberian Branch of the RAS - Division of Federal Research Cen re “The Yakut Scientific Centre of the Siberian Branch of the Russian Academy of Sciences”, Avtodorozhnaya str. 20, Ya kutsk, 677007, Russia Abstract The article presents the studies of the clim te resistance of polyethylene composites containing different stabilizers. To carry out c mplex climatic studies, we chose materials with the highest and most stable mechanical characteristics and de sity. It has been found that the use of sulfur-c ntaining stabilizing additives leads to a color change of the samples fter 1 month f exposure, probably due t the formation of quin e during decomposition of stabilizing additives. It is shown that one of the most s nsitive indicators of polyethylene aging is elongation at rupture. The study of the dependence of el ngation at rupture on the period of exposure in th open air sh wed that the use of stabilizers of grades СО3 and СО 4 in an amount of 0.3-0.5 wt.% is sufficie t to m intain stable work f products an constructions for 1 y ar. Wh reas the original polyethylene an the composite cont ining Stafen stabilizer become embrittled after 9 mo ths of exposure. The electron microscopic studies hav show that t ubmolecular structure of the composites significantly depends on the xposure conditions. Th most prominent cha es in the structural charact ristics were found for the composites exp sed in the open air. Significant temp rature drops during the test period cause these changes. In the general case, it has been found that the use of stabilizers of grades СО3 and СО4 can extend the service life of products and constructions of unpainted polyethylene in the climatic conditions of the Sakha Republic (Yakutia) by 25% (from 9 to 12 months).

© 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ILEE-2019 organizers © 2019 The Author(s). Published by Elsevier B.V. Peer-review under responsibility of the ILEE-2019 organizers © 2019 The Author(s). Published by Elsevier B.V. Peer-review under responsibility of the ILEE-2019 organizers

Keywords: Polyethylene; UV radiation; stabilizers; mechanical characteristics; climatic factors; Keywords: Polyethylene; UV radiation; stabilizers; mechanical characteristics; climatic factors;

* Corresponding author. Tel.: +7-924-662-9045 E-mail address: evgspar@rambler.ru * Corresponding autho . Tel.: +7-924-662-9045 E-mail address: evgspar@rambler.ru

2452-3216 © 2019 The Author(s). Published by Elsevier B.V. Peer-review under responsibility of the ILEE-2019 organizers 2452 3216 © 2019 Th Author(s). Publis d by lsevier B.V. Peer-review under responsibility of the ILEE-2019 organizers

2452-3216 © 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ILEE-2019 organizers 10.1016/j.prostr.2019.12.118