超支化聚合物HP-NH的合成及防塌机理研究

A Study on Anti-collapse Mechanism and Synthesis of Hyperbranched Polymer HP-NH

魏云锦 黄学刚 邹源红 徐伟宁 谢刚

WEIYunjin HUANGXuegang ZOUYuanhong XUWeining XIEGang

中国石油西南油气田公司开发事业部, 四川 成都 610000 中国石油西南油气田公司气田开发管理部, 四川 成都 610000 西南石油大学石油与天然气工程学院, 四川 成都 610500

Development Division, Southwest Oil and Gas Field Company, PetroChina, Chengdu, Sichuan 610000, China Gas Field Development Management Department, Southwest Oil and Gas Field Company, PetroChina, Chengdu, Sichuan 610000, China Petroleum Engineering School, Southwest Petroleum University, Chengdu, Sichuan 610500, China

井壁稳定是当前水基钻井液钻深层页岩气的技术难点。以二乙烯三胺和N，N-亚甲基双丙烯酰胺为原料，通过迈克尔加成反应合成了超支化聚合物HP-NH。采用红外光谱法、液相色谱-质谱联用法、凝胶色谱法、粒度分析法和热失重分析法表征了HP-NH的结构和特征。研究发现，HP-NH的数均分子量为3 371 g/mol，多分散指数为2.7，分子量分布较宽，粒径280～1 900 nm，抗温能力达到280℃。通过线性膨胀实验、回收率实验、泥饼分散实验和“人造泥饼”法分析了HP-NH作为防塌剂的防塌性能。研究表明，随着HP-NH浓度的增加，膨润土的线性膨胀率逐渐降低（最低为19.11%），岩屑的滚动回收率逐渐升高（最高为75.18%），人造泥饼的渗透率逐渐下降。小分子HP NH能够插入蒙脱石的晶层间，交换出层间易水化的阳离子，拉紧基底间距，抑制蒙脱石的水化分散；大分子HP-NH能有效封堵泥饼的微纳米孔缝，起到一剂多用的功效。因此，HP-NH可作为一种潜在的一剂多用防塌剂应用于水基钻井液体系。

Wellbore stability is the current technical difficulty in drilling deep shale gas with water-based drilling fluids. Using diethylenetriamine and N, N-methylenebisacrylamide as raw materials, the hyperbranched polymer HP-NH was synthesized by Michael addition reaction. The structure and characteristics of the hyperbranched polymer HP-NH were characterized by infrared spectroscopy, liquid chromatography-mass spectrometry, gel chromatography, particle size analysis and thermal weight loss analysis. The study found that the number average molecular weight of the hyperbranched polymer HP-NH was 3 371 g/mol, the particle size was in the range of 280～1 900 nm, and the temperature resistance reached 280℃. Through the artificial mud cake method, linear expansion experiment, recovery rate experiment and mud cake dispersion experiment, the anti-collapse performance of hyperbranched polymer HP-NH as an anti-collapse agent was analyzed. We found that with the increase of HP-NH, the linear expansion rate of bentonite gradually decreased (the lowest was 19.11%), the rolling recovery rate of cuttings gradually increased (the highest was 75.18%), and the permeability of the artificial mud cake gradually declined. Hyperbranched polymer HP-NH can be inserted between the crystal layers of montmorillonite to exchange cations that are easily hydrated between the layers, tighten the substrate spacing, and inhibit the hydration and dispersion of montmorillonite; HP-NH can also effectively block mud cake's micro-nano pores. Therefore, the hyperbranched polymer HP-NH can be used as a potential anti-collapse agent in water-based drilling fluid systems.

10.11885/j.issn.16745086.2021.04.30.01