Dynamic surface tensions, foam and the transition from micellar solution to lamellar phase dispersion
Dynamic surface tensions, foam and the transition from micellar solution to lamellar phase dispersion
复制标题
动态表面张力、泡沫以及从胶束溶液到层状相分散体的转变
DOI：
10.1016/0927-7757(95)03218-3
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
P. Gratton
中科院分区：
文献类型：
--
作者：
P. Garrett;P. Gratton
如果表面活性剂在紧密堆积层中的堆积行为被充分改变，则胶束不会形成。在临界聚集浓度下，溶液会变得浑浊，其中发现液晶颗粒分散。这里考虑的这种行为的例子包括低乙氧基化度的十二烷基聚乙二醇醚。还包括从这些化合物与形成胶束的阴离子表面活性剂的混合物或从形成胶束的两性离子表面活性剂与某些形成胶束的阴离子表面活性剂的混合物中沉淀液晶颗粒。可通过测量动态表面张力来监测表面活性剂向空气-水表面的输送速率。含有分散液晶相而不是胶束的溶液表现出向空气-水表面的传输速率降低，这意味着在这些表面处的动态吸附水平相对较低。这导致发泡性降低。然而，所得泡沫的稳定性可增强。这可能是由于液晶材料在Plateau边界的积累导致的体积泡沫排水速率降低所致。这也可能是由于抑制边缘再生而导致泡沫膜排水速率降低。
If the packing behaviour of surfactants in close-packed layers is sufficiently modified then micelles are not formed. Solutions can become turbid at a critical aggregation concentration where a dispersion of liquid crystalline particles is found. Examples of this type of behaviour considered here include dodecyl polyethyleneglycol ethers with low degrees of ethoxylation. The precipitation of liquid crystalline particles either from mixtures of such compounds with micelle forming anionic surfactants or from mixtures of micelle forming zwitterionics with certain micelle forming anionics are also included. Rates of transport of surfactant to air-water surfaces may be monitored by measuring dynamic surface tensions. Solutions containing dispersed liquid crystalline phase, rather than micelles, exhibit diminished rates of transport to air-water surfaces which implies relatively low levels of dynamic adsorption at these surfaces. This leads to diminished foamabilities. However the stability of the resulting foam may be enhanced. This may be caused by diminished bulk foam drainage rates due to accumulation of liquid crystalline material in Plateau borders. It may also derive from diminished foam film drainage rates caused by suppression of marginal regeneration.