文献类型：期刊文献

英文题名：The effect of the spacer rigidity on the aggregation behavior of two ester-containing Gemini surfactants

作者：Zhang, Zhiguo[1];Zheng, Peizhu[1];Guo, Yimin[2];Yang, Yan[1];Chen, Zhiyun[1];Wang, Xiaoyong[1];An, Xueqin[1];Shen, Weiguo[1,2]

机构：[1]E China Univ Sci & Technol, Sch Chem & Mol Engn, Shanghai 200237, Peoples R China;[2]Lanzhou Univ, Dept Chem, Lanzhou 730000, Gansu, Peoples R China

年份：2012

卷号：379

期号：1

起止页码：64

外文期刊名：JOURNAL OF COLLOID AND INTERFACE SCIENCE

收录：;EI(收录号：20122415111780);WOS:【SCI-EXPANDED(收录号:WOS:000305592000010)】；

基金：This work is supported by the National Natural Science Foundation of China (Projects 20973061 and 21173080).

语种：英文

外文关键词：Gemini surfactants; Spacer rigidity; Minimum surface area; Micellization thermodynamics; Aggregation size

摘要：Two Gemini surfactants with very similar structure but different spacer rigidity, namely 1-dodecanaminium,N,N'-[[(2E)-1,4-dioxo-2-butene-1,4-diyl]bis(oxy-2,1-ethanediyl)]bis[N,N-dimethyl-,bromide] (12-fo-12) and 1-dodecanaminium, N.N'-[(1,4-dioxo-1,4-butanediyl)bis(oxy-2,1-ethanediyl)] bis[N,N-dimethyl-, bromide] (12-su-12), and their monomeric counterpart 1-dodecanaminium, N-(2-(acetyloxy)ethyl]-N,N-dimethyl-, bromide (DTAAB) were synthesized and their aggregation behavior in aqueous solutions was studied by measurements of surface tension, conductivity, isothermal titration calorimetry, dynamic light scattering, and transmission electron microscopy. It was found that the Krafft point of 12-fo-12 was 18.6 degrees C, significantly higher than that of 12-su-12 (7.6 degrees C) and DTAAB (<0 degrees C). The minimum surface areas per surfactant A(min) at the water-air interface of DTAAB, 12-su-12, and 12-fo-12 were determined. It was found that the value of A(min) of DTAAB was larger than half that of 12-su-12 but smaller than half that of 12-fo-12. The values of the degree of association beta of the three surfactants were found to be in a sequence of DTAAB > 12-su-12 > 12-fo-12, which was in accord with the sequence of the entropy of micellization. The enthalpies of micellization of the two Gemini surfactants were found to be more negative than double that of DTAAB, and 12-fo-12 had the most negative standard enthalpy of micellization. It was also found that 12-su-12 and DTAAB formed micelles in aqueous solutions, while 12-fo-12 could form micelles and vesicles dependent on the concentration. (C) 2012 Elsevier Inc. All rights reserved.