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Updated: Jul 10, 2026

Characterizing Single-Molecule Conformational Changes Under Shear Flow with Fluorescence Microscopy
Published on: January 25, 2020
Visualization of conformational changes of linear short-chain polyethylenes under shear and elongational flows
J M Kim1, B J Edwards, D J Keffer
1Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, TN 37996-2200, United States.
Abstract:
We have performed nonequilibrium molecular dynamic simulations of the linear short-chain polyethylene liquids C(24)H(50), C(50)H(102), C(78)H(158), and C(128)H(258) under homogenous shear and elongational flows. We present visualizations of the molecular structure of each of the four liquids under shear and elongation, and compare them with their equilibrium static structures. These graphics provide a structural understanding of the various statistical measures that have been used in the literature to characterize the change in chain conformation as a function of strain rate and chain length. Moreover, these graphics allow a visualization of the inherent chain dynamics and orientation induced by shear and elongational flows. We discuss the molecular-level mechanisms apparent in the graphics.
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