Improving the Thermal Stability of Hydrophobic Associative Polymer Aqueous Solution Using a "Triple-Protection" Strategy.

摘要: Because of their high viscoelasticity, Hydrophobic Associative Water-Soluble Polymers (HAWSPs) have been widely used in many industrial fields, especially oilfield flooding and fracturing. However, one major problem which limits the wide applications HAWSPs is weak resistance to temperatures. Once temperature increases over 100 °C, viscosity fracturing fluid decreases rapidly, because temperatures reduce by oxidizing polyacrylamide chains weakening association hydrophobic groups. To improve HAWSP, a triple-protection strategy was developed. First, rigid N-vinyl-2-pyrrolidone moiety introduced into polymer chains. Second, an environmentally-friendly deoxidizer, carbohydrazide, selected prevent oxidization scavenging dissolved oxygen. Results showed that both groups deoxidizer improved helped it maintain under shear rate. Using these two protection strategies, resistant could reach 160 °C. network still got severely damaged at further elevated Therefore, as third strategy, pre-added responsive crosslinking agent applied form new networks The results shown optimized solution kind good up 200