Microscopic understanding of the complex polymer dynamics in a blend -A molecular-dynamics simulation study

作者：Diddens D^*; Brodeck M; Heuer A

来源：EPL, 2011, 95(5): 56003.

DOI：10.1209/0295-5075/95/56003

Within polymer blends composed of two species with largely different glass transition temperatures like PEO/PMMA, the dynamics of the fast PEO component is severely affected by the rather immobile PMMA, reflected by a breakdown of the typical Rouse scaling. The phenomenological random Rouse model (RRM), in which each monomer has an individual mobility obeying a broad log-normal distribution, has been applied to these blends. Using a newly developed method, we extract the distribution of friction coefficients from MD simulations of a PEO/PMMA blend, thereby testing the RRM explicitly. In our simulations we observe that the distribution is much narrower than expected from the RRM. Here, rather, the presence of additional forward-backward correlations of intermolecular origin is responsible for the anomalous PEO behavior.

• 出版日期2011-9