Stability Factors of Foam Film in Contrast to Fluctuation Induced by Humidity Reduction
Stability Factors of Foam Film in Contrast to Fluctuation Induced by Humidity Reduction
复制标题
泡沫膜的稳定性因素与湿度降低引起的波动的对比
DOI：
10.1006/jcis.1997.4819
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发表时间：
1997
影响因子：
9.9
通讯作者：
Nikaido
中科院分区：
文献类型：
--
作者：
Tamura;Kaneko;Nikaido
考察了十二烷基硫酸钠水溶液的动态表面性质与泡沫膜稳定性的关系，考察了动态表面张力(伽马特)、膜层伸长率(L膜)和膜厚度(FT-IR)的变化。通过改变十二烷基硫酸钠浓度的Marangoni效应、添加电解质时的分离压力和添加甘油时的表面粘度等因素，建立了三种泡沫膜模型。为了获得影响泡沫膜稳定性的最重要因素，在低相对湿度条件下对泡沫膜的寿命进行了测量，在低相对湿度条件下泡沫膜发生剧烈波动。在相对湿度为60%-75%的薄水膜中，Marangoni效应和表面剪切粘度显著提高了泡沫膜的稳定性。在此条件下，薄膜会出现轻微的波动。另一方面，在湿度低于60%的情况下，通过在薄水膜中施加分离压力来保持泡沫膜的稳定性。在此条件下，泡沫膜会发生剧烈波动。结果表明，离子表面活性剂溶液的泡沫膜稳定性主要取决于分离压力，分离压力在两个表面之间产生排斥力，而不是由湿度降低引起的剧烈波动。
We have examined the relationship between dynamic surface properties of aqueous SDS solutions and foam film stability by observing the dynamic surface tension (gammat ), elongation of the lamellae (L lamellae ), and the thickness of the lamellae measured by FT-IR. Three foam film models were used by controlling such factors as the Marangoni effect by changing the SDS concentration, the disjoining pressure with the addition of electrolytes, and the surface viscosity with the addition of glycerin. In order to obtain information about the most effective factor in foam film stability, the lifetime of these films was measured under the circumstances of low relative humidity, at which vigorous fluctuation occured in the foam film. Foam film stability was found to be remarkably enhanced by the Marangoni effect and surface shear viscosity in a thin aqueous film at a relative humidity between 60 and 75%. Under these conditions, mild fluctuation would occur in the films. On the other hand, foam film stability was found to be maintained by the disjoining pressure in a thin aqueous film at the humidity below 60%. Under these conditions, vigorous fluctuation would occur in the foam film. It is concluded that foam film stability of an ionic surfactant solution mainly depends on the disjoining pressure which generates a repulsion force between the two surfaces in contrast to the vigorous fluctuation induced by humidity reduction.