Rottach, Dana R.3; Curro, John G.3; Budzien, Joanne4; Grest, Gary S.4; Svaneborg, Carsten1; Everaers, Ralf5
1 Interdisciplinary Nanoscience Center, Faculty of Science, Aarhus University, Aarhus University2 Department of Chemistry, Faculty of Science, Aarhus University, Aarhus University3 Department of Chemical and Nuclear Engineering, University of New Mexico4 Sandia National Laboratories, Albuquerque5 Max Planck Institut für Physik Komplexer Systeme, Dresden
The permanent set of cross-linking networks is studied by molecular dynamics. The uniaxial stress for a bead-spring polymer network is investigated as a function of strain and cross-link density history, where cross-links are introduced in unstrained and strained networks. The permanent set is found from the strain of the network after it returns to the state-of-ease where the stress is zero. The permanent set simulations are compared with theory using the independent network hypothesis, together with the various theoretical rubber elasticity theories: affine, phantom, constrained junction, slip-tube, and double-tube models. The slip-tube and double-tube models, which incorporate entanglement effects, are found to be in very good agreement with the simulations.
Macromolecules, 2006, Vol 39, Issue 16, p. 5521-5530