(574e) Multiscale Modeling of Cellulose Unzipping in Ionic Liquids

Lately, there has been a keen interest in understanding the mechanisms of cellulose dissolution in ionic liquids. Certain ionic liquids have proven quite capable of dissolving cellulose and their low volatility has thrust them in the spotlight as a potential environmentally-friendly solvent. An important aspect of this dissolution process is the detachment of single strands of cellulose from larger crystalline fibers. Atomistic simulations examining small crystalline bundles in ionic liquids have shown both the unzipping of single strand as well as the fraying of the bundle ends. These full atomistic simulations can provide a very high level of detail of the underlying process however at a large computational cost. Ideally, it is of great interest to study much larger strands and much longer times, comparing these values with those determined from experiment. To do this we model these detachment processes through the use of a kinetic Monte Carlo model. Key processes and rates are determined from the smaller, fully atomistic molecular dynamic simulations and incorporated into the kinetic model. In this way it is possible to probe much larger and longer processes throught these key events.