Dynamics and rheology of living polymers

Molecular dynamics simulations are used to study the dynamics and stress relaxation in ``living'' polymers such as wormlike micelles (WLMs) of surfactants. These systems exhibit complex dynamical properties due to incessant chain scission and inter-chain recombination events over time scales that range from few ns to milliseconds. We study the structure and energetics of WLMs obtained from large-scale coarse-grained Molecular Dynamics simulations that consist of millions of atoms. Various dynamical properties such as the non-monotonic variation of the zero shear viscosity with salt concentration, as well as the recombination time and a possible reptation-based stress relaxation mechanism will be discussed.