In order to investigate the high interfacial activity and fair oil phase adaptability of alkanolamide, “1:1” type lauric acid diethanolamide impurities (LDEA) were synthesized and purified by the column chromatography method to obtain dodecanoic acid diethanolamide (C₁₂DEA), ester mixture, etc. The exact structures of these compounds were further confirmed by IR, gas chromatogrph with mass spectroscopy (GC–MS), and NMR. The influence of each component on the interfacial tension of oil/water (IFT) was studied by systematic quantitative analysis. The results showed that (i) the strength of each system to reduce oil/water IFT is C₁₂DEA /DEA ≈ LDEA > C₁₂DEA/DEA/ESTER > C₁₂DEA/NaOH > C₁₂DEA > C₁₂DEA/ESTER > DEA. This indicates that LDEA contributes to the reduction of the oil/water IFT and the enhanced adaptability of crude oil in this order: DEA > > ESTER; (ii) when the IFT of the LDEA/DEA system reached an ultralow value, the minimum content of DEA in the system was 1%, and the maximum ester content was less than 5% when the LDEA/DEA/ESTER system reached the ultralow IFT; (iii) the possible mechanism of effect of LDEA components on the IFT and oil phase adaptability was proposed as the synergistic process among the hydrogen bonding, alkali effect, and interface self‐assembly of molecules in the interfacial layer. The contribution of these three factors were hydrogen bonding > alkali effect > interface self‐assembly.

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链烷醇酰胺（LDEA）降低油水界面张力对不同原油的适应性研究

为了研究链烷醇酰胺的高界面活性和公平的油相适应性，通过柱色谱法合成并纯化了“ 1：1”型月桂酸二乙醇酰胺杂质（LDEA），得到十二烷酸二乙醇酰胺（C ₁₂ DEA），酯混合物，等等这些化合物的确切结构进行了进一步通过IR，气体chromatogrph用质谱法（GC-MS），和NMR确认。通过系统的定量分析研究了每种成分对油/水界面张力的影响。结果表明（i）每个系统降低油/水IFT的强度为C ₁₂ DEA / DEA≈LDEA> C ₁₂ DEA / DEA / ESTER> C ₁₂ DEA / NaOH> C ₁₂DEA> C ₁₂ DEA /酯> DEA 这表明LDEA按以下顺序有助于降低油/水IFT和增强原油的适应性：DEA>> ESTER；（ii）当LDEA / DEA系统的IFT达到超低值时，当LDEA / DEA / ESTER系统达到超低值时，系统中DEA的最低含量为1％，最大酯含量小于5％。 IFT；（iii）提出了LDEA组分影响IFT和油相适应性的可能机制，作为界面层中分子的氢键，碱效应和分子界面自组装之间的协同过程。这三个因素的贡献是氢键>碱效应>界面自组装。