粒子吸附和界面压缩对流体界面表面压力的明显贡献
Yu Fu1, Joelle Frechette1,2
1Chemical and Biomolecular Engineering Department, University of California, Berkeley, Berkeley, California 94760, United States.
Langmuir : the ACS journal of surfaces and colloids
|November 8, 2024
概括
这项研究验证了粒子载体接口的面积替换模型,证实了其在恒定滴水面积条件下的准确性. 当滴水面积发生变化时,会出现偏差,突出显示粒子相互作用和界面形学的影响.
科学领域:
- 体和接口科学科学
- 材料科学 材料科学 材料科学
- 表面化学 表面化学
背景情况:
- 带有粒子的接口对于稳定乳液和泡以及创建先进材料至关重要.
- 区域替代模型描述了粒子如何降低界面张力,但对粒子相互作用的直接验证和理解是有限的.
- 现有的模型往往忽略了粒子-粒子相互作用和界面压缩过程中表面压力的行为.
研究的目的:
- 直接验证粒子负载接口的面积替代模型.
- 为了研究粒子吸附和接口压缩对表面压力和面积分数的影响.
- 为了阐明粒子-粒子相互作用和压缩系统中的界面质学的作用.
主要方法:
- 结合张力计和共聚焦成像来测量吸附能量,表面压力和粒子面积分数.
- 在油水界面上对体颗粒进行的实验.
- 在实验期间,滴水面积和压缩速率的受控变化.
主要成果:
- 当滴水面积保持不变时,面积替代模型在观察到的面积分数范围内得到确认.
- 在粒子吸附过程中滴滴面积的变化导致了与面积替换模型的偏差,在近乎恒定的表面压力下,面积分数增加.
- 界面压缩显示了可以忽略的表面压力变化,高达~0.26的面积分数,其增加归因于更高分数或应变速率的粒子对粒子相互作用.
结论:
- 直接验证在特定条件下支持面积替换模型 (恒定滴滴面积).
- 滴水面积的动态变化显著影响表面压力,并且偏离了简单的面积替换模型.
- 粒子与粒子的相互作用和界面形学是压缩带有粒子的界面时控制表面压力的关键因素.
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