Polymeric Surfactant Stabilized Nanoemulsion Characterization for Enhanced Oil Recovery

Summary Kinetically stable biphasic colloidal dispersion of aqueous phase and oil with average droplet size less than 200 nm are known as Nanoemulsions. Present study investigates the behavior of formulated nanoemulsion by Ultrasonication process using polymeric surfactant (polymethyl ester sulfonate, PMES), n-heptane oil, silica nanoparticle and di-ionized water for enhanced oil recovery application. Polymeric surfactant has dual characteristics of interfacial tension reduction and viscosity enhancement ability that eliminates the drawbacks of surfactant-polymer system. Average droplet size < 200 nm of oil droplets with zeta potential values above −30 mV of the formulated nanoemulsion indicate its high kinetic stability. Unveiling the interactions of oil droplets with PMES surfactant polymer chains and nanoparticles, hence unveiling stabilization mechanism. Pseudo and dilatant behavior of nanoemulsions with stable viscosity values at 70 °C denotes better thermal stability, improved mobility and displacement efficiency. Dynamic rheology analysis show enhanced viscoelastic behavior of nanoemulsion when combined with silica nanoparticles. Study results show a synergetic effect of PMES surfactant and SiO2 nanoparticles with oil droplets signifying enhanced stability and improved rheological behavior of nanoemulsions.