A Review in Polymers for Fluid Loss Control in Drilling Operations.

The ever‐increasing consumption of fossil energy highlights the urgent need to develop technologies to ensure the efficient drilling and exploration of oil and gas resources mainly distributed in deep layers. The complex geological conditions in deep formations with the feature of high temperature, high pressure, and high salinity result in high requirements for the performance of drilling fluids. Various additives are demonstrated to decide the physicochemical properties and functional characteristics of water‐based drilling fluids. As one of the most widely used additives in water‐based drilling fluids, various polymeric filtrate reducers play an important role in minimizing fluid loss, maintaining wellbore stability, ensuring drilling safety and efficiency as well as avoiding formation damage. Herein the design, preparation, and applications of polymer‐based filtrate reducers for fluid loss control in drilling operation are comprehensively summarized. The spotlight is centered on the design strategies and structure–property–performance relationships of polymeric filtrate reducers to minimize fluid loss under high temperature, high pressure, and high salinity conditions. Future perspectives for achieving excellent comprehensive performance are also discussed to motivate new strategies and technologies to design and develop high‐performance drilling fluids with optimal rheological and filtration properties. [ABSTRACT FROM AUTHOR]