Characterization of local dynamics and mobilities in polymer melts —A simulation study

¹ Institut für physikalische Chemie, Westfälische Wilhelms-Universität Münster - Corrensstrasse 28/30, 48149 Münster, Germany, EU
² NRW Graduate School of Chemistry - Corrensstrasse 36, 48149 Münster, Germany, EU
³ Institut für Festkörperforschung, Forschungszentrum Jülich GmbH - 52425 Jülich, Germany, EU

^a d.diddens@uni-muenster.de

Received: 28 May 2010
Accepted: 2 September 2010

Abstract

The local dynamical features of a PEO melt studied by MD simulations are compared to two model chain systems, namely the well-known Rouse model as well as the semiflexible chain model (SFCM) that additionally incorporates chain stiffness. Apart from the analysis of rather general quantities such as the mean square displacement (MSD), we present a new statistical method to extract the local bead mobility from the simulation data on the basis of the Langevin equation, thus providing a complementary approach to the classical Rouse-mode analysis. This allows us to check the validity of the Langevin equation and, as a consequence, the Rouse model. Moreover, the new method has a broad range of applications for the analysis of the dynamics of more complex polymeric systems like comb-branched polymers or polymer blends.