Molecular dynamics simulation of thickening mechanism of supercritical CO2 thickener

Due to small shear viscosity of supercritical carbon dioxide, oil drilling leads to viscous fingering. Addition of polymer as thickener in supercritical CO₂ has been used for improving the sweep efficiency of flooding. The simulated shear viscosity of supercritical CO₂ systems increased with the addition of the polymer. The groups of the polymer have different ability to bind the supercritical CO₂ molecules. The binding effect can mainly be attributed to space grid structure of polymer to reduce movement of CO₂ molecules, in which the van der Waals interaction was the main constraint interaction.