TITLE

Transport properties of polymer melts from nonequilibrium molecular dynamics

AUTHOR(S)
Xu, Z.; de Pablo, Juan J.; Kim, S.
PUB. DATE
April 1995
SOURCE
Journal of Chemical Physics;4/8/1995, Vol. 102 Issue 14, p5836
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
We report new results for polymer melts of bead-spring chain molecules obtained by nonequilibrium molecular dynamics simulations of a Couette flow. The beads of these molecules are connected by finitely extendable nonlinear springs. A multiple time scales algorithm has been extended to nonequilibrium situations for integration of the equations of motion. Our model fluids exhibit shear thinning and nonzero normal-stress differences. We have performed simulations both at constant volume and at constant pressure for melts of linear chains of up to 50 beads. We find that, at constant pressure, the density of long chain melts increases significantly with shear rate. We also report results of simulations for branched chain models. We find that the length of the side groups largely enhances the viscosity at low shear rates. © 1995 American Institute of Physics.
ACCESSION #
7647421

 

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