Synthesis and performance study of the fracturing thickener P(AM/AA/AMPS/NVP/DMAAC-16) for rapid fluid preparation

To meet the requirements of oilfield fracturing operations for rapid working fluid preparation, an emulsion-based thickener, P(AM/AA/AMPS/NVP/DMAAC-16), was synthesized via inverse emulsion polymerization. The synthesis utilized acrylamide (AM), acrylic acid (AA), 2-acrylamido-2-methylpropane sulfonic acid (AMPS), N-vinylpyrrolidone (NVP) and hexadecyl dimethyl allyl ammonium chloride (DMAAC-16) as raw materials was performed. The effects of emulsifier dosage, oil-water ratio, monomer mole ratio, monomer dosage, aqueous phase pH, initiator dosage, reaction temperature, and reaction time and other factors on the experiment were explored through single-factor experiments. The optimal synthesis conditions were determined as follows: an oil-to-water volume ratio of 0.7, the amount of emulsifier is 5 % (relative to the oil phase mass), an initiator concentration of 0.03 % (relative to the total reaction system mass), a reaction time of 4 h, a reaction temperature of 50 °C, an aqueous phase pH of 7, and a total monomer concentration of 35 % of the total system mass, with a molar ratio of n (AM): n(AA): n(AMPS): n(NVP): n(DMAAC-16) = 86.2: 9.7: 3.3: 0.4: 0.4. Furthermore, X-ray diffraction analysis (XRD), infrared spectroscopy analysis (FTIR) and scanning electron microscopy analysis were performed on the polymer product. The characterization results showed that the synthesized product exhibits the characteristics of the target product. The study showed that P(AM/AA/AMPS/NVP/DMAAC-16) polymer exhibits excellent solubility and good application performance, effectively addressing the challenges of moisture absorption, deterioration, long dissolution and preparation time, and complex preparation of powder thickeners in traditional water-based fracturing fluid systems during storage or transportation.