(538a) Molecular Simulation of Cellulose Nanomaterials Near Montmorillonite Clays

Classical molecular dynamics simulations using atomistic force fields were used to fundamentally understand the behavior of cellulose nanomaterials (CNMs) in the proximity of montmorillonite (MMT) clays in presence of seawater. Two types of CNMs were considered, cellulose nanocrystals (CNCs) and cellulose nanofibrils (CNFs, which have no crystalline structure). Our results show that the 100 facet of the CNCs have a strong affinity with the basal surface of the MMT, whereas the 010 facet of the CNC and the CNF have weaker interactions with the MMT. Analysis of hydrogen bonds between the CNMs and the MMT surface reveals that the 100 facet of the CNC has almost 2.5 times more hydrogen bonds than the CNF. These simulation studies give insights into the behavior between CNMs and the MMT, reinforcing experimental studies that suggest that CNMs can be effective additives to water-based drilling fluids used in oil drilling operations. CNMs can create an impermeable barrier that prevent excessive water uptake by the MMT clays in the oil well, which is responsible for significant economic losses (>$500M/year) during drilling operations.