Solution and drilling fluid properties of water soluble AM–AA–SSS copolymers by inverse microemulsion

The present work had the purpose of developing a new class of polymeric additives for water based drilling fluid. The additives were obtained through the copolymerization of acrylamide, acrylic acid and sodium 4-styrenesulfonate (SSS) by inverse microemulsion polymerization. Solution and drilling fluid properties of water-based polymeric drilling fluids were investigated. Results indicate that SSS content in the polymeric drilling fluids has an important impact on the rheological properties, filtrate loss and filter cake morphologies of the polymeric drilling fluid, and the water-based polymeric drilling fluid has a high value of yield point to plastic viscosity, high viscosity, excellent shear thinning and thixotropic behavior, good thermal stability and salt resistance. Hence, it can be used as polymeric drilling fluid under the salty and high temperature environment.