Preparation and Performance Evaluation of Slow-expanding Hydrophobic Polymer Nanomicrospheres

Aiming to solve the problems of the large particle size, high expansion rate of polymer microspheres currently used in anatomical water-plugging technology. In this study, acrylamide (AM), acrylic acid (AA), 2-acrylamido-2-methylpropanesulfonic acid (AMPS), and 4-acrylamido-morpholine (ACMO) were used as the raw materials, and the hydrophobic monomer, hexadecyl dimethyl allyl ammonium chloride (DMAAC-C ₁₆ ), and the cross-linking agent poly(ethylene glycol) 200 diacrylate (PEG200DA). A slow-expanding temperature- and salt-resistant polymer nanomicrospheres (PHM) were prepared by reverse-phase microemulsion polymerization. The PHM structure was characterized using infrared spectroscopy, nuclear magnetic resonance spectroscopy, and scanning electron microscopy, and their properties were analyzed nano-laser particle sizing, and rheometry and employing the filtration factor. Results showed that the average particle size of PHM was 68.69 nm. The swelling multiplicity of PHM microspheres was 4.34 times after four days of dissolution in water at 80°C. The swelling multiplicity after four days of dissolution in mineralized water with a mineralization level of 80,000 mg/L at 25°C was 2.34 times, and the blocking rate was more than 85%. The slow expansion of the synthesized PHM under the high-temperature and high-salt conditions confirmed their good expansion performance. Viscoelasticity test showed that the synthesized PHM had good elasticity and injection properties.