Brownian dynamics simulation of bead–spring chain models for dilute polymer solutions in elongational flow

Abstract

SynopsisWe report results of Brownian dynamics simulations of the steady state and transient rheological behavior of bead and spring chain models in elongational flow. The simulations include examination of the effects of excluded volume, hydrodynamic interactions, chain length, and maximum bond extension. Hydrodynamic interactions are modeled by the Rotne-Prager-Yamakawa tensor. The steady state results for the rheological properties of finitely extensible nonlinear elastic (FENE) chains in the absence of hydrodynamic interactions and excluded volume interactions are compared with the analytic FENE-PM theory of Wedgewood and co-workers. For bead and spring models with short bond lengths, excluded volume and hydrodynamic interactions are shown to affect the steady state rheological properties significantly. 0 1995 Society of Rheology.

Brownian dynamics simulations of star-branched polymers in dilute solutions in extensional flow

“…A slightly increased stress response for the excluded volume star occurs during inception of flow, while steady-state values reach a slightly lower plateau. Similar qualitative behavior has been reported in other Brownian dynamics studies of linear bead-rod and bead-spring systems [35,36]. Moreover, these Brownian dynamics studies have reported that EV interactions are important in determining the initial polymer conformations, which in turn can influence the entire time evolution of polymer configurations.…”

Polymer Melts under Uniaxial Elongational Flow: Stress−Optical Behavior from Experiments and Nonequilibrium Molecular Dynamics Computer Simulations

“…3 Data will be presented for monodisperse polymer melts of N b ) 8400 beads arranged in FENE chains with N ) 30 beads, respectively as well as for the corresponding simple fluid (N ) 1). 2,7 The minimum time steps needed during the simulation runs to prevent chain breaks at different elongation rates are collected in Table 1. 10 The dependence of all quantities on the chain length (degree of polymerization) is not shown here in detail.…”

“…This approach has been extended to flow phenomena such as shear flow 2,3 and elongational flow for polymer melts, 4-6 polymer solutions, 7,8 and more recently, to living polymer systems. For monodisperse amorphous polymer melts, Kremer and Grest 1 have performed extensive equilibrium simulations to investigate the different regimes of the diffusive motion of a polymer chain.…”

On the coarse-graining of polymers into bead-spring chains

“…The technique of Brownian dynamics (BD) [24,25] has been widely used to study the non-equilibrium and equilibrium properties of polymer models in flow, in particular bead-rod and bead-spring models [19,26,27]. Most previous investigations of the behavior of bead-spring chains have used BD.…”