In this paper, a novel series of ester-functionalized cationic Gemini surfactants with amide groups (abbreviated as C m -(BAE)-C m ( m = 12, 14, 16)) were synthesized and their surface tension as well as the thermodynamic surface parameters were determined with conductivity and fluorescence measurements, respectively. The structures of these Gemini surfactants were characterized by FT-IR, 1 H NMR, and MS. The Krafft points of the three surfactants are below 0 °C, indicating better water solubility. The critical micelle concentration (CMC) of these surfactants decreases with the increase in the length of hydrophobic chain. The micellization process of these surfactants was found to be entropy-driven. The polar functional ester groups in the spacer form hydrogen bonds with water molecules, which increases the solubility of these Gemini surfactants in aqueous systems, facilitates the aggregation of their monomers and improves the stability of their micelles.

中文翻译：

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酰胺基酯官能化阳离子Gemini表面活性剂的合成及性能

本文合成了一系列具有酰胺基团的酯官能化阳离子 Gemini 表面活性剂（简称 C m -(BAE)-C m ( m = 12, 14, 16)），并对其表面张力和热力学性能进行了研究。表面参数分别通过电导率和荧光测量来确定。这些 Gemini 表面活性剂的结构通过 FT-IR、1 H NMR 和 MS 进行了表征。三种表面活性剂的克拉夫特点均低于 0°C，表明水溶性较好。这些表面活性剂的临界胶束浓度（CMC）随着疏水链长度的增加而降低。发现这些表面活性剂的胶束化过程是熵驱动的。间隔物中的极性官能酯基与水分子形成氢键，