极性吸附钻井液润滑剂的研究进展与发展趋势

随着深井、超深井、大斜度井、定向井及水平井等复杂井不断增多，高摩阻对于水基钻井液的润滑性能提出了更高的要求。具有极性吸附功能钻井液用润滑剂，能够有效地增强其在摩擦表面的吸附强度，提高钻井液的润滑性能。综述了近年来具有极性吸附功能钻井液用润滑剂，包括醇醚类、植物油酯及其衍生物类、长链烷基葡萄糖苷和极压润滑剂的研究进展。在此基础上，介绍了具有金属钻具表面吸附以及多吸附点功能润滑剂的发展趋势。总体而言，钻井液润滑剂的润滑性能与其结构中的吸附基团的极性、类型与数量具有密不可分的关系。具有较强极性的氨基或酰胺基在钻具或井壁表面的吸附能力强于较弱极性的羟基或醚键。极压润滑基团硫、硼酸酯、以及磷酸酯能够在极压条件下，通过化学反应的形式吸附于钻具金属表面。另一方面，含氮杂环化合物能够牢固地吸附于金属钻具表面，形成络合吸附膜。具有多个极性吸附基团的润滑剂能够在摩擦表面形成多点吸附，可有效增强润滑膜的强度。 

Research Progress Made and Development Trend of Drilling Fluid Lubricants with Polar Adsorption Ability

With more and more deep wells, ultra-deep wells, highly deviated wells, directional wells and horizontal wells drilled worldwide, demands on the lubricity of water base drilling fluids are increasing. Drilling lubricants with polar adsorption ability can effectively enhance the adsorption of the lubricant molecules on the friction surfaces, thereby improving the lubricity of the drilling fluid. This paper summarizes the progress made in the research of drilling lubricants with polar adsorption ability in recent years, including alcohol ethers, vegetable oil esters and their derivatives, long chain alkyl glucosides as well as extreme-pressure lubricants. The development trend of lubricants that can be adsorbed on the surfaces of drilling tools and lubricants with multiple adsorption points are then introduced. Generally speaking, the lubricity of a drilling lubricant is closely related to the polarity, type and quantity of the adsorptive groups in its molecular structure. Amino group and amide group, which have stronger polarity, have better adsorption on the surfaces of drilling tools or borehole walls than hydroxyl group and ether bond which have weak polarity. Under extreme pressures, lubricants containing sulfur, borate or phosphate can be adsorbed on the surfaces of drilling tools through chemical reaction, producing extreme lubricity. Nitrogen-containing heterocyclic compounds, on the other hand, can be adsorbed firmly on the surfaces of drilling tools, forming a complex adsorption film. Lubricants with multiple polar adsorptive groups can form multi-point adsorption on the surfaces of friction, effectively improving the strength of the lubricating film.