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Combining Microfluidics and Microrheology to Determine Rheological Properties of Soft Matter during Repeated Phase Transitions
Published on: April 19, 2018
Viscoelastic phase separation in soft matter and foods
1Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan. tanaka@iis.u-tokyo.ac.jp
Faraday Discussions
|December 14, 2012
Summary
Phase separation in soft matter and foods is driven by viscoelastic forces, not just thermodynamics. Dynamic asymmetry between components dictates pattern formation and material properties.
Area of Science:
- Soft Matter Physics
- Food Science
- Materials Science
Background:
- Phase separation creates heterogeneous patterns in soft matter and foods.
- Traditional understanding focuses on thermodynamic forces like interface tension.
Purpose of the Study:
- To introduce and define "viscoelastic phase separation" as a key mechanism in soft matter and food materials.
- To explain the role of dynamic asymmetry in driving pattern formation.
- To unify various phenomena like network formation, cracking, and gelation under this concept.
Main Methods:
- Analysis of mechanical balance between thermodynamic and viscoelastic forces.
- Identification of dynamic asymmetry sources (size, glass transition temperature).
- Examination of pattern formation in diverse food examples (bread, chocolate, dried foods).
Main Results:
- Viscoelastic forces, arising from dynamic asymmetry, significantly influence morphology.
- Dynamic asymmetry is common in foods due to mixtures of large molecules and liquids.
- Viscoelastic phase separation explains network, cellular, and crack patterns in foods.
- Heterogeneous gels result from the dynamical arrest of this process.
- Links between viscoelastic phase separation, mechanical instability, and fracture are established.
Conclusions:
- Viscoelastic phase separation provides a unified framework for understanding mechanically driven pattern formation in soft matter and foods.
- Dynamic asymmetry is a critical factor in food processing, structure development, and failure.
- This concept offers new perspectives on food texture, stability, and processing.
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