Vinyl Imidazole Sulfonate-based Zwitterionic Copolymers with Tuneable Adsorption on Carbonates

Polymer injection in hydrocarbon reservoirs has been of great interest in petroleum engineering as an enhanced oil recovery (EOR) method. Injection of aqueous solutions of polymers into reservoirs increases the fluid viscosity and reduces its relative permeability in the reservoir, and hence improves volumetric sweep efficiency for EOR applications. However, the flow of polymeric solutions in porous media is subject to some particular effects such as non-Newtonian flow, degradation (thermal, physical, bacterial, and chemical), retention and inaccessible pore volume that are key to evaluating the success of a polymeric flooding. Significant polymer adsorption on the rock surface under high salinity and high temperature reservoir conditions is one of the most major challenges in polymer flooding EOR. Here we report the dynamic adsorption studies of four brine-soluble zwitterionic copolymers containing vinyl imidazole sulfonate using a Quartz Crystal Microbalance and core flooding at high temperatures. Our results indicate that the dynamic adsorption of the polymers on carbonates correlates to their structure variation and fluid properties, and a small presence of certain functional co-monomers on the polymers dramatically changes their dynamic adsorption.