Kawase Tokuzo, Nakagawa Mami, Higuchi Yuuya, Oida Tatsuo
Department of Chemistry and Materials Technology, Kyoto Institute of Technology.
J Oleo Sci. 2015;64(9):971-86. doi: 10.5650/jos.ess15109.
In this study, a series of all-hydrocarbon anionic gemini surfactants containing COOH (adipic acid-type and suberic acid-type), SO3Na, OSO3Na, and OP=O(OH)2 functional groups was developed from 1,4-diol and 1,4-diketone as a key block material. The effect of the surfactant head groups on the surface properties was investigated by surface tension and surface pressure-area (π-A) measurements. We found that the critical micelle concentrations (CMC) of the studied geminis were smaller by one order of magnitude than those of the corresponding 1+l-type surfactants. From π-A measurements, the limiting areas of COOH-type geminis were less than twofold of the area of the corresponding 1+1-type, which indicates that the gemini structure enabled tighter packing than is possible in surfactants of the 1+l-type. In contrast, the limiting area of the OP=O(OH)2-type gemini was larger than those of the COOH-type geminis. Furthermore, the suberic acid-type gemini showed a smaller limiting area than that of adipic acid-type gemini. Therefore, we can conclude that the flexibility of the gemini at the connecting position has a significant effect on formation of the monolayer at the air/water interface.
在本研究中，以1,4 - 二醇和1,4 - 二酮作为关键嵌段材料，开发了一系列含有COOH（己二酸型和辛二酸型）、SO₃Na、OSO₃Na和OP=O(OH)₂官能团的全烃阴离子双子表面活性剂。通过表面张力和表面压力 - 面积（π - A）测量研究了表面活性剂头基对表面性质的影响。我们发现，所研究的双子表面活性剂的临界胶束浓度（CMC）比相应的1 + 1型表面活性剂小一个数量级。从π - A测量结果来看，COOH型双子表面活性剂的极限面积不到相应1 + 1型表面活性剂面积的两倍，这表明双子结构能够实现比1 + 1型表面活性剂更紧密的堆积。相比之下，OP=O(OH)₂型双子表面活性剂的极限面积大于COOH型双子表面活性剂。此外，辛二酸型双子表面活性剂的极限面积小于己二酸型双子表面活性剂。因此，我们可以得出结论，双子表面活性剂在连接位置的柔韧性对空气/水界面单分子层的形成有显著影响。
