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Updated: Jul 11, 2026
08:36
Creating Two-Dimensional Patterned Substrates for Protein and Cell Confinement
Published on: September 6, 2011
Long-range structural order, moiré patterns, and iridescence in latex-stabilized foams
Syuji Fujii1, Anthony J Ryan, Steven P Armes
1Department of Chemistry, Dainton Building, University of Sheffield, Brook Hill, Sheffield, South Yorkshire, S3 7HF, United Kingdom. s.fujii@chem.oit.ac.jp
Journal of the American Chemical Society
|June 15, 2006
Summary
Stable, sterically stabilized polystyrene foams can be easily produced. These foams remain intact after drying, unlike those stabilized by conventional agents, offering potential in security inks.
Area of Science:
- Materials Science
- Colloid and Surface Chemistry
Background:
- Conventional foams often lack long-term stability, especially after drying.
- Stabilizers like sodium dodecyl sulfate or poly(N-vinylpyrrolidone) can be insufficient for robust foam structures.
Purpose of the Study:
- To investigate the facile production of highly stable foams.
- To explore foams stabilized solely by micrometer-sized, sterically stabilized polystyrene (PS) latex particles.
- To evaluate the stability and properties of these PS-stabilized foams.
Main Methods:
- Foam production using sterically stabilized polystyrene latex particles.
- Stability testing in wet and dried states.
- Microscopy techniques including scanning electron microscopy (SEM) and optical microscopy.
Main Results:
- Foams stabilized by PS latex particles exhibited exceptional stability, surviving over a year wet and remaining intact after drying.
- Drying revealed hexagonally close-packed arrays of PS particles, indicating high colloid stability.
- Optical microscopy showed well-defined latex bilayers with long-range order, forming localized moiré patterns.
- Dried foams displayed high iridescence, suggesting potential applications.
Conclusions:
- Sterically stabilized polystyrene latex particles provide superior stabilization for foams compared to conventional agents.
- The ordered structure of dried PS-stabilized foams contributes to their unique optical properties.
- These stable, iridescent foams hold promise for applications in security inks and coatings.
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