通过电场对乳液不稳定性的机械洞察
Alexandra Alicke1,2, Nick O Jaensson2, Jan Vermant1
1Department of Materials, ETH Zurich, Vladimir-Prelog-Weg 5, 8093 Zurich, Switzerland.
Langmuir : the ACS journal of surfaces and colloids
|September 22, 2025
概括
电场通过薄膜来破坏乳液的稳定性,其有效性取决于接口特性. 牛顿黑膜和青膜需要更高的电压进行凝聚,因此需要除剂来有效地破坏稳定.
科学领域:
- 合体和表面科学科学
- 接口现象 接口现象
- 乳液科学 乳液科学
背景情况:
- 稳定的乳液在许多应用中至关重要,但也需要控制不稳定.
- 电场被用来诱导滴滴凝聚,但机制尚未完全理解.
- 影响电凝的因素包括水力动力学,毛细管,分子间力和应力.
研究的目的:
- 调查表面活性和学活性系统中电凝结的机制.
- 确定控制电场对乳液的不稳定性的关键因素.
- 为开发改进的乳液不稳定化策略提供见解.
主要方法:
- 使用修改后的动态薄膜平衡技术来模拟电凝.
- 检查了两个不同的系统:非离子表面活性薄膜 (表面活性) 和青装载薄膜 (质活性).
- 分析了局部薄膜厚度和界面特性对电凝的影响.
主要成果:
- 局部薄膜厚度是电凝的主要决定因素,直接影响麦克斯韦压力.
- 非离子表面活性膜表现出两种模式:水力动力学主导 (低压) 和分子间力稳定 (高压).
- 复杂的青膜在较大的厚度下通过弹性特性稳定,在没有除剂的情况下抵抗电场.
结论:
- 电凝基本上是由局部薄膜厚度和麦克斯韦压力控制的.
- 接口特性显著影响乳液不稳定所需的电场强度.
- 化剂的有针对性的使用可以在具有挑战性的系统中提高电凝效率,例如带青的乳液.
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