页岩压裂用减阻、携砂双功能结构聚合物的动力学分析及制备

Dynamic Analysis and Preparation of Dual-functional Polymer Materials with Drag Reduction and Sand-carrying for Shale Fracturing

孙 圆 周成裕 曾令豪 周 敏 雷茗尧 董洪铎

SUN Yuan ZHOU Chengyu ZENG Linghao ZHOU Min LEI Mingyao DONG Hongduo

为改善压裂液在页岩储层缝网体积压裂前端摩阻大、尾端黏度低的问题，基于分子动力学模拟不同碳链长度孪尾单体的空间位阻、聚合物均方末端距和均方位移。以甲基丙烯酸月桂酯（LMA）、丙烯酰胺（AM）、N，N-二正十二烷基丙烯酰胺（DiC12 AM）为原料，通过胶束聚合方法制备聚合物LMA-DiC12AM-AM（LAD），并对其结构进行表征。利用流变仪和摩阻仪等研究LAD溶液的流变性、减阻性和携砂性。结果表明，DiC12AM单体的空间位阻较小、分子链柔顺性和束缚水分子的能力好，减阻潜力大。LAD具有良好的剪切稳定性（黏度大于75 mPa·s）、剪切恢复性和携砂性，可耐温60 ℃，降阻率达67.4%。聚合物LAD兼具减阻和携砂两种性能，与模拟结果基本一致。

In order to improve the problem of high friction resistance at the front end and low viscosity at the tail end of fracturing fluid in shale reservoir fracture network volume fracturing，the steric hindrance of twin tail monomers with different carbon chain lengths，mean square terminal distance and mean square displacement of polymer materials were simulated based on molecular dynamics. The drag reducer LMA-DiC12AM-AM（LAD）was synthesized by micellar polymerization with lauryl methlacrylate （LMA），acrylamide（AM）and N，N-dodecyl acrylmaide（DiC12AM），then the structure was characterized. The rheological property，drag reduction and sand-carrying capacity of LAD solution were studied by rheometer and friction tester. The results showed that DiC12AM monomer had small steric hindrance，the best chain flexibility of polymer materials molecules，the best ability to bind water molecules，and the great drag reduction potential. LAD had good shear stability（viscosity＞75 mPa·s），shear recovery performance and sand-carrying capacity. The temperature-resistance capacity was up to 60 ℃ ，meanwhile the drag reduction rate reached 67.4%. LAD had both drag reduction and sand-carrying properties，which was basically consistent with the simulation result.

10.19346/j.cnki.1000-4092.2022.03.003