Brownian dynamics simulation of polyelectrolyte dilute solutions under shear flow

The behavior of dilute solutions of linear polyelectrolyte molecules both at equilibrium and under shear flow is modeled by using the Brownian dynamics simulation technique. The mathematical polymer model consists of a bead-and-spring chain with charged beads that interact through a screened Debye-Hückel potential as well as through FENE spring forces. In addition hydrodynamic interaction is included in the simulations. We also illustrate how to parameterize a real polyelectrolyte chain, using as an example the often studied sodium polystyrene sulfonate. This gives us an estimate of the values of the model parameters to be used in the simulations. The dependence of conformational and hydrodynamic properties on salt concentration (parameterized through the Debye length) and on electrostatic strength (related to the degree of ionization) is studied. It is found that the model describes many of the features of polyelectrolyte dilute solutions. © 2006 Wiley Periodicals, Inc.