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Updated: May 25, 2026
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A Testing Platform for Durability Studies of Polymers and Fiber-reinforced Polymer Composites under Concurrent Hygrothermo-mechanical Stimuli
Published on: December 11, 2014
Effect of environmental humidity on static foam stability
Xueliang Li1, Stoyan I Karakashev, Geoffrey M Evans
1Centre for Advanced Particle Processing, University of Newcastle, Callaghan, NSW 2308, Australia.
Langmuir : the ACS Journal of Surfaces and Colloids
|February 7, 2012
Summary
Environmental humidity significantly impacts foam stability. This study reveals humidity accelerates foam collapse, proposing Marangoni instability from uneven evaporation as the cause, supported by bubble bursting observations.
Area of Science:
- Physical chemistry
- Materials science
Background:
- Foam stability is crucial for consumer products like beer and shampoo, and industrial processes such as froth flotation and foam fractionation.
- Understanding factors influencing foam collapse is essential for optimizing these applications.
Purpose of the Study:
- To investigate the effect of environmental humidity on the collapse rate of static foams.
- To propose and experimentally validate a mechanism for humidity-induced foam destabilization.
Main Methods:
- Experiments were conducted to measure foam collapse rates under varying humidity levels.
- High-speed video recording was used to observe the bursting of individual bubbles.
- Microinterferometric methods were employed to study the thinning of isolated foam films at different humidity and temperature conditions.
Main Results:
- A clear dependency between environmental humidity and the rate of foam collapse was demonstrated.
- Experimental observations supported the hypothesis that Marangoni instability, driven by nonuniform evaporation, causes bubble bursting.
- The thinning dynamics of foam films were directly correlated with humidity and temperature variations.
Conclusions:
- Environmental humidity is a critical factor governing foam stability.
- Marangoni instability induced by nonuniform evaporation provides a plausible explanation for humidity-dependent foam collapse.
- Further research into foam film dynamics under varying environmental conditions is warranted.
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