US Patent 9023966 Functional polymer for enhanced oil recovery

The present invention relates compositions and methods for enhanced oil recovery. The method is directed to employing a water-soluble The present invention relates compositions and methods for enhanced oil recovery (EOR). The method is directed to employing a water-soluble functional polymeric surfactant (FPS), with a medium IFT value, preferably ranged from about 0.1 to about 15 dyne/cm between water phase containing polymeric surfactant and hydrocarbon phase, for recovery of hydrocarbons from subterranean formations. The FPS solution demonstrates a strong interaction with oil and the great potential to increase both volumetric sweep efficiency and microscopic displacement efficiency in EOR.