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Updated: Dec 11, 2025
10:17
Patterning of Microorganisms and Microparticles through Sequential Capillarity-assisted Assembly
Published on: November 4, 2021
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Colloidal assembly of polydisperse particle blends during drying.
Yichen Dong1, Nicolas Busatto2, Peter J Roth2
1Department of Materials, Loughborough University, Loughborough, Leicestershire LE11 3TU, UK. i.martin-fabiani@lboro.ac.uk.
Soft Matter
|August 20, 2020
Summary
Polydisperse colloidal blends, containing zwitterionic and acrylic particles, form robust films. Faster drying rates increase zwitterionic particle concentration at the film surface, enhancing material applications.
Area of Science:
- Materials Science
- Colloid Science
- Surface Chemistry
Background:
- Colloidal systems are widely used in coatings and soft products.
- Controlling particle distribution during film formation is crucial for material properties.
- Evaporation rate significantly influences particle segregation in drying colloidal blends.
Purpose of the Study:
- To investigate the self-assembly of polydisperse colloidal blends during film formation.
- To determine the effect of evaporation rate on particle distribution within drying films.
- To explore the potential of polydisperse systems for robust film fabrication.
Main Methods:
- Synthesis of a polydisperse aqueous colloidal system with zwitterionic and acrylic particles.
- Film formation via controlled drying of colloidal dispersions.
- Surface morphology analysis using Atomic Force Microscopy (AFM).
- Sub-surface particle composition analysis using Fourier-Transform Infrared (FTIR) spectroscopy with Attenuated Total Reflection (ATR).
Main Results:
- Zwitterionic particles predominantly cover the film surface across a range of evaporation rates.
- Faster evaporation rates lead to a higher concentration of zwitterionic particles in the film's upper layer.
- Polydisperse systems demonstrate reduced dependence on evaporation rate for particle segregation.
Conclusions:
- Polydisperse colloidal blends offer enhanced control over film surface composition.
- The findings highlight the potential for robust material design in applications where drying conditions vary.
- Understanding assembly mechanisms in polydisperse systems is key for advanced coatings and soft products.
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