Plasma and Fusion Research

Volume 14, 3401106 (2019)

Regular Articles

Structural Changes in Tritium-Substituted Polymeric Materials by Beta Decays: A Molecular Dynamics Study
Haolun LI, Susumu FUJIWARA, Hiroaki NAKAMURA1,2), Tomoko MIZUGUCHI, Takuo YASUNAGA3), Takao OTSUKA4), Takahiro KENMOTSU5), Yuji HATANO6) and Shinji SAITO7)
Graduate School of Science and Technology, Kyoto Institute of Technology, Kyoto 606-8585, Japan
Graduate School of Engineering, Nagoya University, Nagoya 464-8601, Japan
National Institute for Fusion Science, National Institutes of Natural Sciences, Toki 509-5292, Japan
Kyushu Institute of Technology, Iizuka 820-8502, Japan
RIKEN, Wako 351-0198, Japan
Doshisha University, Kyotanabe 610-0394, Japan
University of Toyama, Toyama 930-8555, Japan
Institute for Molecular Science, National Institutes of Natural Sciences, Okazaki 444-8585, Japan
(Received 10 January 2019 / Accepted 10 April 2019 / Published 14 August 2019)


The molecular mechanism through which how beta decays in tritium-substituted species damage DNA and polymeric materials is still unknown. Molecular dynamics simulations of hydrogen-removed polyethylene were performed to predict the structural change of the polyethylene chain after the substituted tritium decays. We calculated the potential energy, the global orientational order parameter, and the average number of consecutive trans bonds. The results are that, the greater the number of removed hydrogen atoms, the higher the potential energy and the lower the value of the global orientational order parameter and the average number of consecutive trans bonds. Thus, after losing hydrogen, polyethylene becomes poorer in terms of both thermal and structural stabilities.


polyethylene, molecular dynamics simulation, beta decay, structural change, tritium

DOI: 10.1585/pfr.14.3401106


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