李新勇 罗攀登 刘坤

摘      要： 以丙烯酰胺、2-丙烯酰胺基-2-甲基丙磺酸、N-丙烯酰吗啉为单体，偶氮二异丁脒盐酸盐为引发剂，去离子水为溶剂，通过自由基聚合，制备了一种三元共聚物，该聚合物具有良好的增黏和耐温抗盐性能。在常规丙烯酰胺类聚合物基础上引入吗啉基团，一方面利用吗啉的环状结构，增强分子的刚性，提升聚合物在高温高盐下的黏度，另一方面利用吗啉基单元良好的抑制水解能力，提升聚合物老化稳定性能。通过单因素实验，考察了单体比例、单体质量分数、引发剂用量、反应时间对于产物增黏性能的影响，得到了最优的聚合条件，评价了聚合物的抗盐和抗老化性能。结果表明：聚合物的耐盐性能优良，在110 ℃下老化20 d后的黏度为12.6 mPa·s，展现出良好的抗老化性能。

关  键  词：提高采收率;聚丙烯酰胺衍生物;耐温抗盐;表观黏度;驱油剂

中图分类号：TE 357       文献标识码： A       文章编号： 1671-0460（2020）05-0838-05

Abstract： A terpolymer was prepared by radical polymerization using acrylamide， 2-acrylamide-2- methylpropanes- ulfonic acid and N-acrolylmorpholine as monomers， 2，2'-azobis（2-methylpropionamidine） dihydrochloride as initiator， and deionized water as solvent. This polymer has good viscosity-increasing ability， and presents excellent properties of salt-resistance and heat-tolerance. Based on the molecular structure of conventional polyacrylamide derivatives， morpholine groups with ring structure were introduced to enhance the rigidity of the molecule， and the viscosity of the polymer under high temperature and high salinity was increased. In addition， the polymer aging stability could be improved due to its good ability to inhibit hydrolysis. The effect of monomer ratio， monomer mass fraction， initiator amount， and reaction time on product properties was investigated through single factor experiments， and the optimal polymerization conditions were obtained. The performance of the polymer was evaluated. The results indicated that the salt-resistance of the polymer was excellent， and it also exhibited good heat-tolerance because its viscosity was 12.6 mPa·s after aging at 110 ℃ for 20 d.

Key words： Enhanced oil recovery; Polyacrylamide derivatives; Salt-resistance and heat-tolerance; Apparent viscosity;  Oil displacement agent

聚合物驅是一种重要的提高原油采收率技术，在大庆油田、胜利油田、渤海油田等油田取得了很好的现场应用效果[1，2]。聚合物驱主要的化学药剂为水溶性聚合物，最常用的为部分水解聚丙烯酰胺（HPAM）及衍生物[3]。聚合物驱油的机理是通过增加注入地层流体的黏度，改变油水的流度比，抑制驱替过程中的指进现象，提高注入流体的波及系数;此外，聚合物溶液的黏弹性可以促进油滴从岩石表面剥离，对于洗油效率具有一定的提升效果[4-6]。

在高温条件下，聚合物的水化能力降低，分子线团的尺寸降低;分子之间氢键等相互作用被削弱，聚合物分子网架结构强度降低;老化过程中聚合物水解度增加，在钙镁离子作用下聚合物容易沉淀[7-9]。……