The purpose of this paper is to comprehend in‐depth the effect of the surfactant structure on its and physicochemical properties such as surface/interfacial properties, foam stability, wettability, and biodegradability. To this end, quaternary ammonium Gemini surfactants, alkanediyl‐α,ω‐bis[(2‐hydroxypropyl)dodecylammonium] dibromide (abbreviated as C_m‐n‐C_m[iso‐Pr(OH)]₂ with m = 12, 14 and n = 2, 3, 4) were synthesized via substitution and quaternization reactions, and their chemical structures were characterized by Fourier transform infrared (FT‐IR) and nuclear magnetic resonance (¹HNMR) spectroscopies. The results showed that with the decrease of the spacer length, the surface tension was reduced more strongly, and with the increase of the alkyl tail length, micelles were more easily formed. Besides, the highest surface activity of C₁₄‐2‐C₁₄[iso‐Pr(OH)]₂ was observed by increasing NaCl concentration to 200 g L⁻¹. The temperature had a great influence on thermodynamic parameters of the adsorption and micellization. The interfacial tension between 0.26 g L⁻¹ C₁₄‐2‐C₁₄[iso‐Pr(OH)]₂ solution and oil could reach 0.022 mN m⁻¹. An elongation of the spacer chain in C₁₄‐n‐C₁₄[iso‐Pr(OH)]₂ was unfavorable to foam stability. Besides, the oil‐wetted core, which was aged in 0.6 g L⁻¹ C₁₄‐2‐C₁₄[iso‐Pr(OH)]₂ solution, exhibited more hydrophilicity. C_m‐n‐C_m[iso‐Pr(OH)]₂ surfactants produced higher biodegradable rates in river water (≥ 90% after 28 days) than the biodegradable surfactant of international recommendation (71% after 28 days) at 30 °C.

中文翻译：

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具有2-羟基丙基的极性首基的新型季铵盐双子表面活性剂的合成及表面性质

本文的目的是深入了解表面活性剂结构对其表面化学特性（例如表面/界面特性，泡沫稳定性，润湿性和生物降解性）的影响。为此，使用季铵盐Gemini表面活性剂，烷二基-α，ω-双[（2-羟丙基）十二烷基铵]二溴化物（缩写为C _m -n-C _m [iso-Pr（OH）] ₂，m = 12、14 （n = 2，3，4）是通过取代和季铵化反应合成的，其化学结构通过傅立叶变换红外（FT-IR）和核磁共振来表征（¹HNMR）光谱学。结果表明，随着间隔物长度的减少，表面张力更强烈地降低，而随着烷基尾部长度的增加，胶束更容易形成。此外，通过将NaCl浓度增加到200 g L ^-1，可以观察到C ₁₄ -2-C ₁₄ [iso-Pr（OH）] ₂的最高表面活性。温度对吸附和胶束化的热力学参数有很大的影响。0.26 g L ^-1 C ₁₄ -2-C ₁₄ [iso-Pr（OH）] ₂溶液与油之间的界面张力可能达到0.022 mN m ^-1。C _14中间隔链的延伸‐n‐C ₁₄ [iso-Pr（OH）] ₂不利于泡沫稳定性。此外，在0.6 g L ^-1 C ₁₄ -2-C ₁₄ [iso-Pr（OH）] ₂溶液中老化的浸油核表现出更大的亲水性。C _m n n C _m [iso-Pr（OH）] ₂表面活性剂在30°C时在河水中产生的生物降解率（28天后≥90％）比国际推荐的生物降解表面活性剂（28天后71％）更高。 。