سنتز و مشخصه‌يابي ميكروژل‌هاي حساس به دما (آب درخشان) بر پايه پليمرهاي مصنوعي جهت كاهش توليد آب از مخازن نفت

In this study, the design an‎d synthesis of temperature-activated microgels for simultaneous water shutoff an‎d production control in reservoirs are presented. The microgels were synthesized via the inverse emulsion polymerization method. The selec‎ted materials were prepared in two organic an‎d aqueous pHases. The aqueous pHase consisted of acrylamide (AM), 2-acrylamido-2-methylpropane sulfonic acid (AMPS), N, N′-methylenebisacrylamide (MBA), ammonium persulfate (APS), trimethylolpropane triacrylate (TMPTA), an‎d sodium hydroxide (NaOH), while the organic pHase contained cyclohexane an‎d two nonionic surfactants, Span 60 an‎d Tween 80. After synthesis, three samples with different molar ratios were prepared, an‎d sixteen experiments were designed for each sample. The effects of pH, particle size, an‎d the weight ratio of additives on the equilibrium swelling behavior of the samples were optimized at ambient temperature (25 °C) an‎d reservoir-simulated temperature (101 °C) in both distilled water an‎d saline water (40,000 ppm). Synthesis 1, exhibiting a swelling ratio of 147 times its initial weight an‎d stability over 28 days, was selec‎ted as the optimal sample. The optimized microgel was characterized using thermogravimetric analysis (TGA), field emission scanning electron microscopy (FESEM), dynamic light scattering (DLS), an‎d rheometry. Microscopic observations revealed that the optimized sample consisted of interconnected spHerical particles an‎d exhibited thermal stability up to 250 °C. Furthermore, the synthesized microgel demonstrated high mechanical strength in saline water (40,000 ppm) at 90 °C. Notably, the elastic modulus of the sample in suspension at 90 °C was measured to be 800 Pa. The dominance of the elastic modulus over the viscous modulus, along with its independence from applied strain an‎d frequency, indicates the viscoelastic behavior of the microgel. According to the results obtained during the research, a temperature-sensitive microgel with the ability to respond to temperature stimuli, with a porous structure an‎d resistant to water salinity (40,000 ppm), was prepared. As was observed, in the sample with the highest crosslinking agent (Synthesis 3), the difference in swelling rate at 25°C an‎d 101°C is very large, the reason for this is the very high density of pores an‎d the very strong network bond of the sample, which causes the inability of water to enter an‎d increase swelling. After the destruction of the unstable crosslinking agent after reaching the critical temperature (design temperature), a sufficient capacity for water retention is created in the microgel structure an‎d the maximum swelling is reached, which confirms the results of the equilibrium swelling test well.

حميدرضا شاه وردي , محسن محمدي

نازنين مختاري

روح اله هاشمي , مرضيه عليدادي