文章基本信息

标题：Boson peak, elasticity, and glass transition temperature in polymer glasses: Effects of the rigidity of chain bending
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作者：Naoya Tomoshige ; Hideyuki Mizuno ; Tatsuya Mori 等
期刊名称：Scientific Reports
电子版ISSN：2045-2322
出版年度：2019
卷号：9
期号：1
页码：1-13
DOI：10.1038/s41598-019-55564-2
出版社：Springer Nature
摘要：The excess low-frequency vibrational spectrum, called boson peak, and non-affine elastic response are the most important particularities of glasses. Herein, the vibrational and mechanical properties of polymeric glasses are examined by using coarse-grained molecular dynamics simulations, with particular attention to the effects of the bending rigidity of the polymer chains. As the rigidity increases, the system undergoes a glass transition at a higher temperature (under a constant pressure), which decreases the density of the glass phase. The elastic moduli, which are controlled by the decrease of the density and the increase of the rigidity, show a non-monotonic dependence on the rigidity of the polymer chain that arises from the non-affine component. Moreover, a clear boson peak is observed in the vibrational density of states, which depends on the macroscopic shear modulus G. In particular, the boson peak frequency ω BP is proportional to [Formula: see text]. These results provide a positive correlation between the boson peak, shear elasticity, and the glass transition temperature.