Dai Caili, Xu Zhongliang, Wu Yining, Zou Chenwei, Wu Xuepeng, Wang Tao, Guo Xu, Zhao Mingwei
School of Petroleum Engineering, State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580, China.
Polymers (Basel). 2017 Jul 21;9(7):296. doi: 10.3390/polym9070296.
: Water-soluble polymers are widely used in oilfields. The rheological behaviors of these polymers in high-salinity solution are very important for stimulation of high-salinity reservoirs. In this work, a novel thermal-resistant and shear-stable amphoteric polyacrylamide (PASD), prepared from acrylamide (AM), sodium styrene sulfonate (SSS), and acryloxyethyl trimethylammonium chloride (DAC) monomers, was prepared by free-radical polymerization in high-salinity solution. The amphoteric polyacrylamide was characterized by Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance spectroscopy (¹H NMR), elemental analysis, thermogravimetric analysis (TG), and scanning electron microscopy (SEM). The amphoteric polyacrylamide exhibited excellent salinity tolerance. The slow increase in apparent viscosity of the polymer with increase in salinity was interesting. The amphoteric polyacrylamide showed perfect temperature resistance in high-salinity solution. The viscosity retention reached 38.9% at 120 °C and was restored to 87.8% of its initial viscosity when temperature was decreased to room temperature. The retention ratio of apparent viscosity reached 49.7% at 170 s and could still retain it at 25.8% at 1000 s. All these results demonstrated that PASD had excellent thermal-resistance and shear-stability in high-salinity solution. We expect that this work could provide a new strategy to design polymers with excellent salinity-tolerance, thermal-resistance, and shear-stability performances.
水溶性聚合物在油田中被广泛应用。这些聚合物在高盐溶液中的流变行为对于高盐油藏的增产措施非常重要。在本研究中，通过自由基聚合法在高盐溶液中制备了一种由丙烯酰胺（AM）、苯乙烯磺酸钠（SSS）和丙烯酰氧乙基三甲基氯化铵（DAC）单体合成的新型耐热且抗剪切的两性聚丙烯酰胺（PASD）。通过傅里叶变换红外光谱（FTIR）、核磁共振光谱（¹H NMR）、元素分析、热重分析（TG）和扫描电子显微镜（SEM）对两性聚丙烯酰胺进行了表征。该两性聚丙烯酰胺表现出优异的耐盐性。聚合物的表观粘度随盐度增加而缓慢上升，这一现象很有趣。两性聚丙烯酰胺在高盐溶液中表现出良好的耐热性。在120℃时粘度保留率达到38.9%，当温度降至室温时恢复到初始粘度的87.8%。在170 s时表观粘度保留率达到49.7%，在1000 s时仍能保持在25.8%。所有这些结果表明PASD在高盐溶液中具有优异的耐热性和抗剪切稳定性。我们期望这项工作能够为设计具有优异耐盐性、耐热性和抗剪切稳定性的聚合物提供一种新策略。
