Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE A nanomaterial-reinforced preformed particle gel (NR-PPG) with a robust three-dimensional network is developed by incorporating KH570-modified nano-silica into a NaAA/AMPS/ACMO copolymer matrix. The reinforced structure provides enhanced swelling stability, mechanical toughness, and environmental adaptability, enabling effective particle migration, deformation, and pore-throat plugging under harsh reservoir conditions.

ABSTRACT
To address the challenges of insufficient mechanical strength and limited environmental adaptability of conventional preformed particle gels (PPGs) under harsh reservoir conditions, a nanomaterial-reinforced preformed particle gel (NR-PPG) was developed in this study. NR-PPG was synthesized through aqueous copolymerization of sodium acrylate (NaAA), 2-acrylamido-2-methylpropanesulfonic acid (AMPS), and 4-acryloylmorpholine (ACMO) using KH570-modified nano-silica as a reinforcing component. The incorporation of nano-silica and the synergistic effects of ionic and nonionic monomers endowed NR-PPG with enhanced structural stability and environmental adaptability. The synthesized NR-PPG was characterized by FTIR, SEM, and DLS, confirming the successful modification of nano-silica and its uniform dispersion within the polymer network. The optimized NR-PPG exhibited stable swelling behavior over a wide range of pH, salinity, and temperature conditions, maintaining excellent swelling capacity under simulated reservoir conditions (120°C and 1 × 104 mg/L salinity). Rheological analysis revealed a predominantly elastic response and stable three-dimensional network structure. Moreover, NR-PPG achieved a compressive strength of 2422.6 kPa, elongation at break of 2404%, and tensile strength of 147 kPa, demonstrating a combination of high strength and toughness. These results indicate that NR-PPG is a promising candidate for high-temperature and high-salinity oilfield water shutoff applications.