Johari-Goldstein heterogeneous dynamics in a model polymer

Francesco Puosi; Antonio Tripodo; Marco Malvaldi; Dino Leporini

doi:10.1021/acs.macromol.1c00066

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arXiv · 2102.12527

Johari-Goldstein heterogeneous dynamics in a model polymer

Francesco Puosi·Antonio Tripodo·Marco Malvaldi·Dino Leporini

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Abstract

The heterogeneous character of the Johari-Goldstein (JG) relaxation is evidenced by molecular-dynamics simulation of a model polymer system. A double-peaked evolution of dynamic heterogeneity (DH), with maxima located at JG and structural relaxation time scales, is observed and mechanistically explained. {The short-time single-particle displacement during JG relaxation weakly correlates with the long-time one observed during structural relaxation}.

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Francesco Puosi, Antonio Tripodo, Marco Malvaldi, Dino Leporini. 2021-02-24. Johari-Goldstein heterogeneous dynamics in a model polymer. https://doi.org/10.1021/acs.macromol.1c00066

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