Skip to main content
Article
Energetic and Entropic Elasticity of Nonisothermal Flowing Polymers: Experiment, Theory, and Simulation
Journal of Rheology (2008)
  • David Keffer, University of Tennessee - Knoxville
  • T. C. Ionescu, University of Tennessee - Knoxville
  • B. J. Edwards, University of Tennessee - Knoxville
  • V. G. Mavrantzas
Abstract

The thermodynamical aspects of polymeric liquids subjected to nonisothermal flow are examined from the complementary perspectives of theory, experiment, and simulation. In particular, attention is paid to the energetic effects, in addition to the entropic ones, that occur under conditions of extreme deformation. Comparisons of experimental measurements of the temperature rise generated under elongational flow at high strain rates with macroscopic finite element simulations offer clear evidence of the persistence and importance of energetic effects under severe deformation. The performance of various forms of the temperature equation are evaluated with regard to experiment, and it is concluded that the standard form of this evolution equation, arising from the concept of purely entropic elasticity, is inadequate for describing nonisothermal flow processes of polymeric liquids under high deformation. Complete temperature equations, in the sense that they possess a direct and explicit dependence on the energetics of the microstructure of the material, provide excellent agreement with experimental data.

Keywords
  • deformation,
  • elasticity,
  • entropy,
  • polymers
Publication Date
2008
Publisher Statement
Copyright (2008) American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics.
Citation Information
David Keffer, T. C. Ionescu, B. J. Edwards and V. G. Mavrantzas. "Energetic and Entropic Elasticity of Nonisothermal Flowing Polymers: Experiment, Theory, and Simulation" Journal of Rheology Vol. 52 Iss. 1 (2008)
Available at: http://works.bepress.com/david_keffer/10/