Research on LCST-type temperature-sensitive polymers and their application progress in drilling fluids

Low critical solvation temperature (LCST) temperature-sensitive polymers are temperature-sensitive polymers whose chains present a stretch solution state before the phase transition temperature and a shrink aggregation state after the phase transition temperature. With intelligent and reversible response to ambient temperature change, LCST have been widely studied in the fields of organic chemistry, materials science, biomedicine, and oil and gas industry. In this review, LCST-type temperature-sensitive polymers with different spatial conformations were categorized, with a focus on the research progress on LCST-type temperature-sensitive polymers with linear structures, temperature-sensitive hydrogels, block structures, grafted composite structures and special structures. The application status quo of LCST-type temperature-sensitive polymers with different spatial conformations in drilling fluids, such as low-temperature rheology control, temperature-sensitive intelligent plugging, viscosity enhancement and cutting, and leakage prevention and plugging, were summarized. Finally, the key problems of LCST-type temperature-sensitive polymers and their application prospects in the field of drilling fluids were discussed. © 2024 Fine Chemicals. All rights reserved.