当前位置: X-MOL 学术Phys. Chem. Chem. Phys. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Characterization of the micelle structure of oleic acid-based gemini surfactants: effect of stereochemistry†
Physical Chemistry Chemical Physics ( IF 3.3 ) Pub Date : 2018-03-12 00:00:00 , DOI: 10.1039/c8cp00396c
Tadashi Sugahara 1, 2, 3, 4, 5 , Yuichiro Takamatsu 5, 6, 7 , Avinash Bhadani 3, 4, 5, 8 , Masaaki Akamatsu 1, 2, 3, 4, 5 , Kenichi Sakai 1, 2, 3, 4, 5 , Masahiko Abe 3, 4, 5, 8 , Hideki Sakai 1, 2, 3, 4, 5
Affiliation  

In this study, we synthesize a novel oleic acid-based gemini surfactant with carboxylate headgroups, and study the effect of stereochemistry (anti- vs. syn-) on self-aggregation properties in water. We investigate these properties using phase diagrams, static surface tension, and one-dimensional and two-dimensional nuclear magnetic resonance (NMR) measurements. We find that a phase transition from a hexagonal liquid crystal (H1) phase to a lamellar liquid crystal (Lα) phase occurs at a lower surfactant concentration in the syn form, when compared with the anti form. In addition, the syn form gemini surfactant forms micelles with a close packing of the headgroups via hydrogen bonding. This was supported by static surface tensiometry; the area occupied by surfactant molecules at the air/aqueous solution interface is smaller for the syn form than for the anti form. We propose that, for the syn form gemini surfactant, the closer packing of the headgroups as well as the hydrogen bonding network around the micelle interface prevent water penetration into the hydrophobic part of the micelle.

中文翻译:

基于油酸的双子表面活性剂胶束结构的表征:立体化学的影响

在这项研究中,我们合成了一种新的具有羧酸根基的油酸基双子表面活性剂,并研究了立体化学(---)对水中自聚集性能的影响。我们使用相图,静态表面张力以及一维和二维核磁共振(NMR)测量来研究这些特性。我们发现,与相比,以较低的表面活性剂浓度在顺式中会发生从六方液晶(H 1)相到层状液晶()相的相变。另外,syn形成双子表面活性剂通过氢键形成与头基紧密堆积的胶束。这是由静态表面张力测定法支持的。表面活性剂分子在空气/水溶液界面处所占的面积对于式来说要比式要小。我们建议,对于顺式双子表面活性剂,头基的紧密堆积以及胶束界面周围的氢键网络可防止水渗透到胶束的疏水部分。
更新日期:2018-03-12
down
wechat
bug