A Review of Research Progress and Prospects of <scp> CO ₂ </scp> ‐Responsive Polymers and Gels for Profile Control and Plugging

ABSTRACT CO 2 ‐responsive polymers, which undergo reversible reactions with CO 2 through specific functional groups, allow for the intelligent switching between hydrophilic and hydrophobic states. This property shows great potential for applications in oil and gas extraction. This review first elucidates the fundamental response mechanisms of CO 2 ‐responsive polymers and recent advances in plugging and profile control technologies for CO 2 flooding. It then systematically summarizes the research progress in profile control and plugging over the past five years, including CO 2 ‐responsive random and graft copolymers. Furthermore, recent advances in polymer gels for profile control and plugging are reviewed, categorized into four types: CO 2 ‐responsive in situ gels, microgels, pre‐crosslinked particle gels, and polymer microspheres. Finally, future research directions are highlighted, emphasizing the development of temperature‐ and salt‐tolerant CO 2 ‐responsive materials, the establishment of standardized performance evaluation protocols, and the advancement of multi‐stimuli responsive systems to facilitate large‐scale application in realistic reservoir environments.