Effect of hypergravity on the modification of xanthan gum

To improve the properties of xanthan gum (XG), 3-chloro-2-hydroxypropyltrimethylammonium chloride and propylene oxide were used as modifiers to etherify XG and to obtain cationic hydroxypropyl xanthan gum (HCXG), and cationic hydroxypropyl xanthan gum (CHCXG), further optimized by super-gravity reaction. The structure of the product was characterized by infrared spectroscopy and nuclear magnetic resonance. The rheological properties of XG, HCXG, and CHCXG solutions and their performance as fracturing fluids were studied. Infrared and nuclear magnetic test results showed that the cationic etherification agent and hydroxypropyl group were successfully connected to XG, and the degree of substitution of CHCXG was higher. The rheological properties of the CHCXG solution and the performance of the fracturing fluid base fluid were superior to those of the XG and HCXG solutions. The viscosity of the solution after the super-gravity modification was further increased, and the apparent viscosity of the 0.4% CHCXG solution was 28.96% higher than that of the HCXG solution. After XG modification, the solution strength, yield stress, viscoelasticity, temperature resistance, and shear resistance were all significantly improved. The rheological properties of the HCXG solution and the performance of the fracturing fluid base fluid are good and can be used for fracturing fluid thickener.