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Updated: Jun 19, 2026
11:52
Microbubble Fabrication of Concave-porosity PDMS Beads
Published on: December 15, 2015
Effect of adsorbed polymers on bubble--particle attachment
Audrey Beaussart1, Luke Parkinson, Agnieszka Mierczynska-Vasilev
1Ian Wark Research Institute, ARC Special Research Centre for Particles and Material Interfaces, University of South Australia, Mawson Lakes, SA 5095, Australia.
Langmuir : the ACS Journal of Surfaces and Colloids
|October 29, 2009
Summary
Adsorbed dextrin-based polymers significantly impact bubble-particle attachment in talc flotation. Polymer effects on wetting film rupture and dewetting rates, not equilibrium contact angles, correlate with flotation recovery.
Area of Science:
- Mineral processing
- Surface chemistry
- Colloid science
Background:
- Bubble-particle attachment is crucial for mineral flotation.
- Adsorbed polymers can alter surface properties and affect flotation performance.
- Understanding polymer-surface interactions is key to optimizing talc recovery.
Purpose of the Study:
- To investigate the influence of adsorbed dextrin-based polymers on air bubble attachment to talc.
- To correlate polymer adsorption characteristics with talc flotation recovery.
- To elucidate the mechanisms governing polymer-induced changes in bubble-particle interactions.
Main Methods:
- Dynamic contact angle measurements.
- Liquid film rupture studies.
- Talc flotation recovery tests.
- Analysis of adsorbed polymer layer morphology.
Main Results:
- Adsorbed polymers play a major role in bubble-particle attachment.
- No direct link found between equilibrium contact angle and flotation recovery.
- Strong correlations observed between flotation recovery and wetting film rupture time/dewetting rate.
- Retardation of three-phase contact line expansion by polymers significantly influences attachment.
Conclusions:
- Wetting film dynamics, specifically rupture time and dewetting rate, are critical indicators of polymer influence on talc flotation.
- The morphology of the adsorbed polymer layer affects wetting film behavior and bubble-particle attachment.
- Optimizing polymer adsorption for enhanced wetting film stability can improve talc flotation recovery.
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