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Collective Motion in the Interfacial and Interior Regions of Supported Polymer Films and Its Relation to Relaxation
Published
Author(s)
Wengang Zhang, Francis W. Starr, Jack F. Douglas
Abstract
We investigate the extent of collective motion in the interfacial regions of a thin supported polymer film and within the film interior by molecular dynamics simulations to understand the role of collective motion in the often large changes in interfacial molecular mobility observed in polymer films. Contrary to commonly stated expectations, we find that the extent of collective motion determining the temperature dependence of the structural relaxation time does not vary significantly within the film, a finding consistent with Adam-Gibbs proposal that the extent of collective motion in glass-formingliquidsisrelatedtotheconfigurationalentropy, a thermodynamic property that cannot vary with position within the film.
Zhang, W.
, Starr, F.
and Douglas, J.
(2019),
Collective Motion in the Interfacial and Interior Regions of Supported Polymer Films and Its Relation to Relaxation, Journal of Physical Chemistry B
(Accessed October 11, 2025)