How the flow affects the phase behaviour and microstructure of polymer nanocomposites
Abstract
We address the issue of flow effects on the phase behaviour of polymer nanocomposite melts by making use of a recently reported Hamiltonian set of evolution equations developed on principles of nonequilibrium thermodynamics. To this end, we calculate the spinodal curve, by computing values for the nanoparticle radius as a function of the polymer radiusofgyration for which the second derivative of the generalized free energy of the system becomes zero. Under equilibrium conditions, we recover the phase diagram predicted by Mackay et al. [Science 311, 1740 (2006)]. Under nonequilibrium conditions, we account for the extra terms in the free energy due to changes in the conformations of polymer chains by the shear flow. Overall, our model predicts that flow enhances miscibility, since the corresponding miscibility window opens up for nonzero shear rate values.
 Authors:
 Department of Mathematics and Statistics, University of Cyprus, P.O. Box 20537, 1678 Nicosia (Cyprus)
 Publication Date:
 OSTI Identifier:
 22416131
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Chemical Physics; Journal Volume: 142; Journal Issue: 6; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; EQUILIBRIUM; FREE ENERGY; HAMILTONIANS; MICROSTRUCTURE; NANOCOMPOSITES; PHASE DIAGRAMS; POLYMERS; SHEAR; SOLUBILITY; THERMODYNAMICS
Citation Formats
Stephanou, Pavlos S., Email: stephanou.pavlos@ucy.ac.cy. How the flow affects the phase behaviour and microstructure of polymer nanocomposites. United States: N. p., 2015.
Web. doi:10.1063/1.4907363.
Stephanou, Pavlos S., Email: stephanou.pavlos@ucy.ac.cy. How the flow affects the phase behaviour and microstructure of polymer nanocomposites. United States. doi:10.1063/1.4907363.
Stephanou, Pavlos S., Email: stephanou.pavlos@ucy.ac.cy. 2015.
"How the flow affects the phase behaviour and microstructure of polymer nanocomposites". United States.
doi:10.1063/1.4907363.
@article{osti_22416131,
title = {How the flow affects the phase behaviour and microstructure of polymer nanocomposites},
author = {Stephanou, Pavlos S., Email: stephanou.pavlos@ucy.ac.cy},
abstractNote = {We address the issue of flow effects on the phase behaviour of polymer nanocomposite melts by making use of a recently reported Hamiltonian set of evolution equations developed on principles of nonequilibrium thermodynamics. To this end, we calculate the spinodal curve, by computing values for the nanoparticle radius as a function of the polymer radiusofgyration for which the second derivative of the generalized free energy of the system becomes zero. Under equilibrium conditions, we recover the phase diagram predicted by Mackay et al. [Science 311, 1740 (2006)]. Under nonequilibrium conditions, we account for the extra terms in the free energy due to changes in the conformations of polymer chains by the shear flow. Overall, our model predicts that flow enhances miscibility, since the corresponding miscibility window opens up for nonzero shear rate values.},
doi = {10.1063/1.4907363},
journal = {Journal of Chemical Physics},
number = 6,
volume = 142,
place = {United States},
year = 2015,
month = 2
}

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