UR1268 Biopolymères Interactions Assemblages, INRA, équipe Interfaces et Systèmes Dispersés, F-44316 Nantes, France.
Langmuir. 2010 Apr 20;26(8):5329-34. doi: 10.1021/la9034613.
We report on dispersions of fatty acid-lysine salts in aqueous solutions which are further used to produce foams. The alkyl chain length is varied from dodecyl to stearic. In aqueous solutions, the lysine salt of the dodecyl chain yields an isotropic solution, probably micelles, whereas for longer alkyl chains, vesicles formed but crystallized upon resting at room temperature or when kept at 4 degrees C. Solid-state NMR showed that in vesicles fatty acids are embedded in a lamellar arrangement passing from a gel to a fluid state upon heating; the transition temperature at which it occurs was determined by DSC. Those results are confirmed by small-angle neutron scattering which also give additional information on the bilayer structure. Incredibly stable foams are obtained using the palmitic acid/Lys salt whereas for other alkyl chain length, poor or no foam is formed. We conclude that the foamability is related to the phase behavior in aqueous solution.
我们报告了脂肪酸赖氨酸盐在水溶液中的分散情况，这些分散体进一步用于制备泡沫。烷基链的长度从十二烷基变化到硬脂基。在水溶液中，十二烷基链的赖氨酸盐生成各向同性溶液，可能是胶束，而对于更长的烷基链，形成了囊泡，但在室温下静置或在 4°C 下保存时会结晶。固态 NMR 表明，在囊泡中，脂肪酸嵌入层状排列中，在加热时从凝胶态转变为流态；通过 DSC 确定发生该转变的温度。这些结果得到了小角中子散射的证实，小角中子散射还提供了关于双层结构的其他信息。使用棕榈酸/赖氨酸盐可以获得难以置信的稳定泡沫，而对于其他烷基链长度，则形成较差或没有泡沫。我们得出结论，泡沫形成能力与水溶液中的相行为有关。
