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Combining Microfluidics and Microrheology to Determine Rheological Properties of Soft Matter during Repeated Phase Transitions
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Entropic patchiness drives multi-phase coexistence in discotic colloid-depletant mixtures
Á González García1,2, H H Wensink3, H N W Lekkerkerker2
1Laboratory of Physical Chemistry, Department of Chemical Engineering and Chemistry, & Institute for Complex Molecular Systems (ICMS) Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven, The Netherlands.
Scientific Reports
|December 8, 2017
Summary
Hard particle dispersions with anisotropic shapes exhibit complex phase behaviors due to excluded volume effects. Free volume theory explains these phenomena, including rich phase diagrams for platelet mixtures with depletants.
Area of Science:
- Thermodynamics
- Soft Matter Physics
- Colloid Science
Background:
- Hard particle dispersions' phase behavior is governed by excluded volume interactions.
- Anisotropic particles, unlike spheres, display complex multi-phase equilibria.
- Depletants introduce entropic patchiness, leading to orientation-dependent attractions.
Purpose of the Study:
- To demonstrate the utility of free volume theory for understanding anisotropic particle systems.
- To rationalize experimental findings in complex phase behavior.
- To investigate the phase behavior of platelet-depletant mixtures.
Main Methods:
- Application of free volume theory to anisotropic hard particles.
- Analysis of excluded volume arguments and entropic effects.
- Modeling of platelet-depletant mixtures.
Main Results:
- Free volume theory successfully incorporates excluded volume and depletant effects.
- Anisotropic particles exhibit richer phase behavior than spheres.
- Platelet-depletant mixtures show extensive three-phase coexistence and quadruple regions.
Conclusions:
- Free volume theory provides a simple, generic framework for complex phase behavior.
- Understanding anisotropic particle interactions is crucial for materials science applications.
- Platelet-depletant systems offer a rich platform for studying multi-phase equilibria.
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