Influence of salt concentration on shear thickening properties of LPS

Linked polymer solution (LPS) is a new type of profile control agent, and its flow behavior in oil reservoirs is one of the key factors influencing profile control effect. The shearing function of porous media in oil reservoirs is simulated using the Ostwald viscosity meter. The variation of LPS flow behavior is studied under different salt concentrations and repeated shearing conditions. Combined with rheology, the correlation between the phenomenon of shear thickening and the dispersion of LPS midline group (LPC) is analyzed. Experimental results show that within a certain concentration range of NaCl, LPS system gets shear thickening at the definite reaction time, with the increase of NaCl concentration, while the reaction time required for shear thickening is shortened. It also shows that the ratio of intramolecular cross-linking of polymer and cross-linking agents and the number of LPC increase with the increase of salt concentration. This provides a new method feasible for the study of cross-linking process of low-concentration polymer cross-linking systems.