Session W18 - Computer Simulation II.
ORAL session, Thursday morning, March 15
Room 308-308, Washington State Convention Center
We have studied a variety of polymer stretching problems using equilibrium and non-equilibrium Molecular Dynamics (MD) simulations with explicit solvent. These problems include the stretching of polymer chains in strong flows, the effects of confinement on hydrodynamic drag, the difference between the stress and the strain ensemble when pulling the two ends of a linear chain apart, and the transition from the freely-jointed chain (FJC) to the worm-like chain. Our results disagree with the predictions of the FJC models for flow-induced stretching, but not for mechanical stretching. We also demonstrate that an important delay in hydrodynamic interactions exists that is not considered by any current model. Finally, we observe a short-time scale ballistic regime for the free relaxation of stretched chains.