(226as) Investigating the Effective Parameters in the Coil-Stretch Transition of High Molecular Weight Polystyrene Under Uniaxial Extensional Flow: A Hi-Fidelity Brownian Dynamics Approach

Excluded volume and hydrodynamic interactions play a central role in macromolecular dynamics under equilibrium and non-equilibrium settings. The high computational cost of incorporating the influence of hydrodynamic interaction in meso-scale simulation of polymer dynamics has motivated much research on development of high fidelity and cost efficient techniques. Among them, the Chebyshev polynomial based techniques and the Krylov subspace methods are most promising. To this end, in this study we have developed a series of semi-implicit predictor-corrector Brownian dynamics algorithms for bead-spring chain micromechanical model of polymers that utilizes either the Chebyshev or the Krylov framework. The algorithm with the highest efficiency and fidelity, namely, the Krylov subspace method, is used to simulate dilute solutions of high molecular weight polystyrene in uniaxial extensional flow [L. Li, R. G. Larson, and T. Sridhar, J. Rheol. 44, 291 (2000)]. Finally, the influence of different parameters, namely appropriate inclusion of excluded volume (EV) and hydrodynamic interactions (HI), the level of fine-graining, the type of EV potential, and the type of conservative spring force law on the observed extensional hardening of polystyrene dilute solutions over a broad molecular weight range will be discussed.