| CPC C09K 8/588 (2013.01) [C08F 212/20 (2020.02); C08F 220/06 (2013.01); C08F 220/22 (2013.01); C08F 220/24 (2013.01); C08F 220/56 (2013.01); E21B 43/20 (2013.01); C09K 2208/10 (2013.01)] | 20 Claims |

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1. A method comprising:
pumping a mixture through a wellbore into a geological formation, the mixture comprising a surfactant, salt, water, and polymer nanoparticles comprising core-shell nanoparticles each having a core and a shell, wherein the core comprises a polystyrene center, and wherein the shell comprises a zwitterionic group and a fluoro functional group covalently attached to the core; and
flowing the mixture through the geological formation, wherein the pumping and the flowing comprise enhanced oil recovery (EOR) comprising flooding, wherein the flooding of the geological formation increases oil recovery from a reservoir in the geological formation, and wherein:
the flooding comprises nanofluid flooding; and
the fluoro functional group comprises at least one of the following structures:
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