Decoupling of mass transport mechanisms in the stagewise swelling of multiple emulsions.
Decoupling of mass transport mechanisms in the stagewise swelling of multiple emulsions.
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多重乳液分阶段溶胀中传质机制的解耦
DOI：
10.1021/acs.langmuir.5b01138
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
Windhab
中科院分区：
文献类型：
--
作者：
Hughes;Pokorny;Riesch;Fischer;Windhab
这篇文章报道了不平衡水包油包水（W1/O/W2）乳液的传质动力学。虽然经常研究，但W1/O/W2乳液中的传质控制仍然具有挑战性。我们描述了一种基于微流体的方法，系统地研究了各种参数，如渗透压梯度，油相粘度和温度对传质的影响。结合光学显微镜分析，我们能够识别和解耦的各种机制，控制动态液滴大小的不平衡的W1/O/W2乳液。因此，生成了具有非常高精度的溶胀动力学曲线，为量化运输的动力学方面提供了基础。两个连续的膨胀阶段，即，一个滞后阶段和一个主导阶段，具有不同的质量传输机制被确定。不同阶段的确定和解释是控制和触发膨胀过程的前提。我们表明，这两个质量传输机制可以相互解耦的证据。快速的热驱动的质量传递仅发生在第二阶段，该第二阶段由滞后阶段中的油相的结构变化引起，这允许两个水相之间的渗透交换。自发的油包水乳化强烈促进了这种结构变化。滞后阶段的持续时间与压力无关，但受油相粘度和温度的显著影响。
This contribution reports on the mass transport kinetics of osmotically imbalanced water-in-oil-in-water (W1/O/W2) emulsions. Although frequently studied, the control of mass transport in W1/O/W2 emulsions is still challenging. We describe a microfluidics-based method to systematically investigate the impact of various parameters, such as osmotic pressure gradient, oil phase viscosity, and temperature, on the mass transport. Combined with optical microscopy analyses, we are able to identify and decouple the various mechanisms, which control the dynamic droplet size of osmotically imbalanced W1/O/W2 emulsions. So, swelling kinetics curves with a very high accuracy are generated, giving a basis for quantifying the kinetic aspects of transport. Two sequential swelling stages, i.e., a lag stage and an osmotically dominated stage, with different mass transport mechanisms are identified. The determination and interpretation of the different stages are the prerequisite to control and trigger the swelling process. We show evidence that both mass transport mechanisms can be decoupled from each other. Rapid osmotically driven mass transport only takes place in a second stage induced by structural changes of the oil phase in a lag stage, which allow an osmotic exchange between both water phases. Such structural changes are strongly facilitated by spontaneous water-in-oil emulsification. The duration of the lag stage is pressure-independent but significantly influenced by the oil phase viscosity and temperature.
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DOI：
10.1111/j.1467-2494.1992.tb00045.x
发表时间：
1992-01-01
影响因子：
2.3
作者：
TADROS T F
通讯作者：
TADROS T F
微乳液的热力学：液滴分散熵和表面活性剂膜弯曲能的综合影响
DOI：
--
发表时间：
1980
期刊：
影响因子：
--
作者：
Clarence A. Miller;P. Neogi
通讯作者：
P. Neogi
DOI：
--
发表时间：
1970
期刊：
影响因子：
--
作者：
C. Miller;L. Scriven
通讯作者：
L. Scriven
DOI：
--
发表时间：
1972
期刊：
影响因子：
--
作者：
D. Shah;A. Tamjeedi;J. Falco;R. Walker
通讯作者：
R. Walker
影响因子：
9.9
作者：
N. Garti;S. Magdassi;D. Whitehill
通讯作者：
N. Garti;S. Magdassi;D. Whitehill