Organosilicate Polymer As High Temperature Resistent Inhibitor for Water-Based Drilling Fluids

In this study, the inhibition property of an organosilicate polymer was investigated as an inhibitor for water-based drilling fluids. A novel polymer was prepared using 2-acrylamido-2-methylpropane sulphonic acid (AMPS), N, N-dimethyl acrylamide (DMAA), maleic anhydride (MA), and γ-methacryloxypropyl trimethoxy silane (MEMO) as the polymerisation monomers, named as ADMM. Also, the inhibition performance was evaluated by an immersion test, a linear swelling test, and a shale cuttings recovery test. Compared with that of the other inhibitors, the addition of ADMM can effectively inhibit the swelling of mud balls, resulting in the lowest swelling height of the drilling fluid. ADMM was characterised using a thermogravimetric analysis, a Fourier transform infrared spectrometer, a nuclear magnetic resonance instrument, a laser particle size distribution instrument, and a zeta potentiometric analyser. The results showed that the decomposition temperature of ADMM was 330 °C. The shale cuttings recovery of the 1.0% ADMM solution at 150 °C was 76.32%. The dynamic shear rise rate was as low as 160%. Furthermore, ADMM was adsorbed on the clay surface at many points to form a “protective film” of the polymer, thus inhibiting the hydration of the clay.