针对常规聚丙烯酰胺微球膨胀过快导致其在运移过程中发生剪切破碎、封堵效率降低的问题,以丙烯酰胺(AM)、丙烯酸(AA)、聚乙二醇二丙烯酸酯400、酸处理淀粉、屏蔽剂为原料,采用反相乳液聚合的方法合成了一种耐剪切能力强、膨胀速率可控的新型互穿网络微球调驱剂。考察了淀粉质量分数对微球粒径的影响以及屏蔽剂浓度对微球膨胀性能的影响。利用红外光谱、热重、扫描、透射及驱替实验对产物的结构、形貌以及性能进行了分析。结果表明,当淀粉质量分数为4‰、屏蔽剂浓度为2 mol/L时,合成的互穿网络微球凝结率低,微球粒径保持在63.94 nm左右,膨胀速率由1 600%降至170%,岩心封堵效率由89.4%提高至96.6%。对岩心驱替实验前后微球微观形貌进行观察发现,其形貌基本不变,表现出良好的耐剪切性能。

Conventional polyacrylamide microsphere expands too fast,which leads to shear breakage in the process of migration and reduces the sealing efficiency.A kind of novel interpenetrating network microspheres with strong shear resistance and controllable expansion rate is synthesized by inverse emulsion polymerization method using acrylamide (AM),acrylic acid (AA),polyethylene glycol acrylate 400,acid-treated starch and shielding agent as raw materials.The effect of starch concentration on the particle size of microspheres and the effect of addition of shielding agent on expansion property of microspheres are investigated.The structure,morphology and properties of the microspheres are analyzed by means of infrared,thermogravimetric,scanning,transmission and displacement experiments.Results show that when the mass content of starch is 4‰ and the concentration of shielding agent is 2 mol·L^-1,the condensation rate of the synthesized microspheres is low,the particle size is about 63.94 nm,the expansion rate decreases from 1,600% to 170%,and the core blocking efficiency increases from 89.4% to 96.6%.The microspheres' micromorphology before and after the core displacement experiment is hardly changed,showing a good shear resistance.

宋昭杰(1984-),男,硕士,工程师,研究方向为油田助剂,szj_cq@petrochina.com.cn;赖小娟(1984-),女,博士,教授,研究方向为功能高分子材料的合成研究,3578466@163.com。