Abstract
A hydrophobic associating active polymer (acrylic acid [AA]/ acrylamide [AM]/ α‐sodium alkenesulfonate [AOS]/ dimethyloctadecyl allyl ammonium chloride (DMAAC
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) was synthesized via aqueous solution polymerization, using AA, AM, AOS, and DMAAAC
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as the main monomers, with ammonium persulfate‐sodium bisulfite as the initiator. The optimal synthesis conditions for AA/AM/AOS/DMAAC
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were as follows: total monomer concentration of 30%, initiator dosage accounting for 0.46% of the total monomer mass, reaction temperature of 50°C, and reaction time of 4 h. The chemical structure of AA/AM/AOS/DMAAC
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was characterized by Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance spectroscopy (
1
H NMR), and scanning electron microscopy (SEM). Its performance properties, including viscosity behavior, shear resistance, temperature tolerance, salt resistance, and emulsifying capacity, were systematically evaluated. Experimental results indicated that the apparent viscosity of the AA/AM/AOS/DMAAC
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solution prepared with injected water at 30°C was significantly higher than that of a polyacrylamide (HPAM) solution at the same concentration. After 30 s of mechanical shearing at 28,000 r/min, the viscosity retention rate of the 3000‐mg/L AA/AM/AOS/DMAAC
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solution (86.2%) was 34.17% higher than that of the HPAM solution at the same concentration (52.03%). Additionally, AA/AM/AOS/DMAAC
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exhibited excellent emulsifying performance and a stronger ability to reduce oil–water interfacial tension. Under identical experimental conditions, HPAM and AA/AM/AOS/DMAAC
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enhanced oil recovery by 10.67% and 16.88%, respectively, demonstrating that AA/AM/AOS/DMAAC
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possesses superior oil displacement efficiency.