Coarse-grained modeling of macromolecular solutions using a configuration-based approach

An accurate, configuration-based, coarse-grained model for dilute macromolecular solutions is presented. The basic approach relies on exploring the macromolecular configurational diversity present in the flow of dilute polymeric solutions and identifying and partitioning the most frequently observed configurations, e.g., folds, half dumbbells, kinks, dumbbells, coils, and stretched states. The probability of finding any one of these configurations is calculated using a master configuration map that dictates the conditional probability of finding a configuration with a given chain extension. Each configuration class is modeled using a dumbbell description with a suitably modified drag coefficient. The configuration-based model is implemented using a Brownian dynamics simulation and the predictions are compared with the corresponding bead-spring model and finitely extensible nonlinear elastic dumbbell in homogeneous steady shear and uniaxial extension. Finally, prospects for model improvement are discussed.