Synthesis and Surface Properties of Novel Carboxylic Ester-Containing Imidazolium-Based Zwitterionic Surfactants: Monoalkyl 2-(3-Methylimidazolium-1-yl) Succinate Inner Salts

摘要

A series of carboxylic ester-containing imidazolium-based zwitterionic surfactants, namely, monoalkyl 2-(3-methylimidazolium-1-yl) succinate inner salts (C(n)MimSU, n = 8, 10, 12 and 14), have been synthesized. Their structures were confirmed by H-1 NMR, C-13 NMR and FTIR. The typical physicochemical properties parameters such as isoelectric point, critical micelle concentration (CMC), surface tension at CMC (gamma (CMC)), surface pressure at CMC (I (CMC)), adsorption efficiency (pC (20)), the maximum surface excess (I" (m)), the minimum molecular cross-sectional area (A (min)) and the value of CMC/C (20) were determined. The effect of the long-chain length on the important physicochemical properties of C(n)MimSU was studied. It is found that the surface activity of C(n)MimSU is enhanced with the long-chain length increases.