Effects of Ion on the Properties of Seawater Slurry and Development of Salt-Tolerant Polymer Seawater Slurry

To address the significant deterioration in the performance of traditional drilling slurries due to seawater intrusion, this study developed a novel salt-tolerant polymer slurry (MXC) utilizing grafting modification techniques. The performance of MXC was systematically evaluated and compared with two commercial slurries, PAC and Flowz, through simulated formation filtration experiments. The results indicate that the MXC slurry exhibited the lowest filtration loss and was capable of forming a thinner, denser filter cake, thereby providing optimal wall protection. Mechanistic analysis revealed that grafting modification optimized the hydrophobic interactions between polymer molecules, constructing a dynamic physical cross-linking network and a rigid double-helical structure within the solution. This significantly enhanced the system’s viscosity and resistance to ionic interference, ultimately resulting in the formation of a dense network structure during the filtration process. This study offers a novel material solution and theoretical foundation for the development of high-performance salt-tolerant slurries in marine engineering.