Optimizing Nanosilica-Enhanced Polymer Synthesis for Drilling Fluids via Response Surface Methodology: Enhanced Fluid Performance Analysis

In this study, nanosilica-based polymers were synthesized and optimized for water-based drilling fluid applications using response surface methodology (RSM). The synthesis process involved the polymerization of methacryloyloxyethyl trimethyl ammonium chloride (DMC), methacrylic acid (MAA), and silane-modified nanosilica (KH570-SiO2) under varying conditions of temperature, initiator concentration, and pH. Characterization by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (1H-NMR), thermogravimetric analysis, and optical microscopy confirmed the successful polymerization and incorporation of nanosilica while maintaining structural integrity and thermal stability. The reaction conditions were optimized using RSM with variables including the temperature, pH, and initiator concentration. The optimized conditions (70.9 °C, pH 7, and 0.57 wt.% initiator concentration) resulted in significant enhancements in drilling fluid performance, including a 46.0% reduction in filtration loss, a 28.6% decrease in coefficient of friction (CoF), and improved cutting-carrying capacity (YP/PV ratio). Post-reaction analyses demonstrated the thermal stability and reusability of the synthesized polymers under high-temperature conditions, confirming their applicability in field operations. This work highlights the potential of nanosilica-based polymers in improving drilling fluid performance, offering insights into optimization strategies and enhanced material stability.