Application of Graphene Oxide/Polymer Composites as Filter Loss Reduction Agents With Water‐Based Drilling Fluids

ABSTRACT In deep and ultra‐deep wells, drilling fluids often experience increased filtration loss due to elevated temperatures and high salinity. To solve this problem, 5 g of N, N‐dimethylacrylamide (DMAA), 13 g of 2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid (AMPS), 2 g of 4‐acryloylmethiolane (ACMO), and 0.2 g of graphene oxide (GO) were polymerized through aqueous phase polymerization at 50°C for 2 h to form the Graphene oxide and DMAA, AMPS, ACMO Composites (GO‐NAA). The synthesized nanocomposite, GO‐NAA, was characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance, and thermogravimetric analysis to confirm its structure. The experimental results showed that under the conditions of 220°C and 15% NaCl, water‐based drilling fluid (WBDF) containing 3% GO‐NAA reduced the filtration value of the American Petroleum Institute(FLAPI) by 82.15% (from 76.2 to 13.6 ml) and the high‐temperature and high‐pressure filtration value (FLHTHP) by 88.50% (from 238.2 to 27.4 ml) compared to water‐based drilling fluid without GO‐NAA. Morphological analysis revealed that GO‐NAA adhered to bentonite particles through hydrogen bonding and electrostatic interactions, promoting uniform dispersion of particles in the aqueous drilling fluid. This mechanism facilitated the formation of a thin and dense mud cake, which effectively minimized filtration loss. These findings quantitatively demonstrate the potential of GO‐NAA as a temperature‐ and salt‐resistant filtration loss reduction agent, offering significant performance improvements under extreme drilling conditions.