Spatial Dependence of Molecular Relaxation in Deformed Polymers
ORAL
Abstract
We present a general framework for investigating the spatial and temporal dependence of structural anisotropy relaxation in deformed polymers by combining small-angle neutron scattering and the spherical harmonic expansion technique. Experiments on polymer melts over a wide range of molecular weights reveal that their conformational relaxation at relatively high momentum transfer (Q) and short time can be described by a simple and universal scaling law, with the relaxation rate proportional to Q. This scaling behavior, while further confirmed by coarse-grained molecular dynamics simulations, does not seem to stem from either the Rouse or reptative motions depicted in the classical models, and calls for further development in the theory of polymeric liquids under deformation and flow.
*This research was sponsored by the Laboratory Directed Research and Development Program of Oak Ridge National Laboratory, managed by UT Battelle, LLC, for the U.S. Department of Energy. This work was conducted at the Center for Nanophase Materials Sciences, the Spallation Neutron Source, and the Oak Ridg
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Presenters
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Yangyang Wang
- Oak Ridge National Lab
- Oak Ridge National Laboratory