一种非离子疏水缔合聚丙烯酰胺的合成及性能评价

Synthesis and Performance Evaluation of a Nonionic Hydrophobically Associated Polyacrylamide

为了开发一种速溶性非离子疏水缔合聚合物,将易水溶的非离子表面活性剂型疏水单体十八烷基聚乙二醇1100甲基丙烯酸酯与丙烯酰胺共聚反应得到一种非离子型疏水缔合聚丙烯酰胺,采用核磁共振氢谱分析了合成聚合物的结构,利用激光光散射仪测定了合成聚合物的相对分子质量,并考察了合成聚合物的增黏性和耐温耐剪切性能。研究表明,所合成的二元共聚物的相对分子质量为3.18×10^6g/mol,黏度法测得的临界缔合浓度约为0.23%,SDS能显著提高溶液黏度。在剪切速率170s^-1下,质量分数0.4%的合成聚合物溶液,在50数90℃下,由于疏水缔合作用的增强,黏度有明显上升;随温度进一步升高,黏度下降;在150℃下剪切30min后的黏度仍高于50mPa·s。扫描电镜分析表明,聚合物在常温下形成的网状结构较高温的致密。所合成的疏水缔合聚合物有作为压裂液增稠剂使用的应用前景。

In order to develop a fast-soluble nonionic hydrophobic associative polymer,a water-soluble nonionic surfactant-type hydrophobic monomer,octadecyl polyethylene glycol 1100 methacrylate,was copolymerized with acrylamide at 55℃. The polymer was successfully proved by using 1H NMR. The molecular weight was measured by static light scattering,and the performance of the viscosity increasing,heat resistance and salt tolerance of the obtained polymer was measured. The results showed that the molecular weight of the polymer was 3.18×10^6 g/mol and the critical association concentration was determined to be about 0.23% by the viscosity method,the addition of SDS would increase the viscosity of the solution obviously. The viscosity of 0.4% polymer solution was increased significantly at a shear rate of 170 s^-1. when the temperature increasing from 50℃ to 90℃, due to the enhanced hydrophobic association;and the viscosity decreased with increasing temperature. The viscosity was still higher than 50 mPa·s after sheared for 30 min at the temperature of 150℃,which indicated that the obtained polymer had good heat resistant and salt tolerant performance. Scanning electron microscopy analysis showed that the network formed at room temperature was denser than at 100℃. The obtained hydrophobically associated polyacrylamide has potential applications as a thickener of fracturing fluid.