钻井液与完井液2023，Vol.40Issue(6)：749-755,764,8.DOI:10.12358/j.issn.1001-5620.2023.06.008
多巴仿生润滑剂在水基钻井液中的应用及机理研究
Application and Mechanisms of Dopa Biomimetic Lubricant in Water Based Drilling Fluids
摘要
Abstract
A Dopa biomimetic lubricant L2,3 for water based drilling fluids was developed with Dopa which has strong adhesive capacity in water environment,and this new lubricant is expected to be able to solve the problem of poor lubrication performance of ester lubricants in water because of the poor adhesivity of the esters on the surfaces of drilling tools in water.Another lubricant L2,5 with phenolic hydroxyl groups on different positions in the molecules of the lubricant was also synthesized and characterized by FT-IR and 1H NMR.The lubricity and wear resistance of the two lubricants were evaluated using extreme pressure lubricity tester,mud cake adhesion coefficient tester,four-ball friction tester and SEM.L2,3 in sodium bentonite(Na-BT)based fluid has the best lubricity,the coefficient of friction(COF)of an Na-BT based fluid treated with 1%L2,3 is as low as 0.07,a percent reduction of COF of 87.7%,and the wear scar diameter(WSD)is 0.587 mm.At temperatures less than 210℃ ,the base fluid has good lubricity and does not foam.The L2,5 lubricant,on the other hand,has goo lubricity in fresh water,with COF of 0.1,while in Na-BT based fluid,the lubrication film of the lubricant is unable to resist the shear of the clay particles and is damaged,and the COF is 0.57,a value close to the COF of the blank base fluid.Analyses of the components and thickness of the lubrication film with XPS show that the phenolic hydroxyl groups help enhance the adhesion ability of the lubricant on the surfaces of the metals,hence improving the lubricity and wear resistance of the lubricant.The performance of the lubricants has a relation to the type of the phenolic hydroxyls.The L2,3,which contains catechol structure,can form a dense organic film of 80 nm in thickness on the surfaces of a metal through bidentate metal coordination bonds,while L2,5 containing para-hydroxyl groups can only form a film of less than 20 nm on the surfaces of the metal.Compared with the L2,5 lubricant,the L2,3 lubricant has better lubricity and wear resistance because it can form more stable bidentate metal coordination bonds on the surfaces of metals.关键词
水基钻井液/仿生润滑剂/环境友好/双齿金属配位键Key words
Water based drilling fluid/Biomimetic lubricant/Environmentally friendly/Bidentate metal-ligand bonds分类
能源科技引用本文复制引用
杨旭坤,蒋官澄,贺垠博,董腾飞..多巴仿生润滑剂在水基钻井液中的应用及机理研究[J].钻井液与完井液,2023,40(6):749-755,764,8.基金项目
国家自然科学基金青年科学基金项目"智能钻井液聚合物处理剂刺激响应机理与分子结构设计方法研究"(52004297). （52004297）
