Synthesis of novel copolymer based on N-Vinyl caprolactam and acrylamide monomers for high temperature drilling applications

Drilling fluids are considered as blood of drilling industry for the extraction of oil and gas. Many chemical additives are employed to formulate drilling fluids, but water-soluble polymers play vital role to adjust rheological and filtration properties. Natural and conventionally used polymers in drilling fluids show degradation at high temperature drilling applications. For this purpose, a novel copolymer based on N-Vinyl caprolactam and acrylamide monomers was synthesized for high temperature application of drilling fluids. The chemical structure and composition of copolymer was analyzed using Fourier transform spectroscopy. The suitability of copolymer for drilling fluid formulation was determined by performing rheological properties with different concentrations at temperature ranging from 75°F to 150°F. The steady shear rheology experiments showed that increasing the concentration copolymer in the base drilling fluid resulted in significant increase in viscosity, shear stress and gel strength of modified drilling fluid. While increasing the temperature of modified drilling fluid up to 150°F with increasing copolymer concentration, the rheological properties (shear stress and viscosity) shows no prominent change compared to the modified drilling fluid (B). The synthesized novel copolymer with N-Vinyl caprolactam and acrylamide monomers can be used to formulate drilling fluid for high temperature applications.