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Combining Microfluidics and Microrheology to Determine Rheological Properties of Soft Matter during Repeated Phase Transitions
Published on: April 19, 2018
Fluid-fluid transitions at bulk supercritical conditions
Fei Xie1, Clifford E Woodward, Jan Forsman
1Theoretical Chemistry, Chemical Centre, Lund University, P.O. Box 124, S-22100 Lund, Sweden. fei.xie@teokem.lu.se
Langmuir : the ACS Journal of Surfaces and Colloids
|January 31, 2013
Summary
Capillary-induced phase separation can occur in pores under supercritical conditions, even without surface transitions. This finding, derived from polymer solvent mixture models, has implications for adsorption in porous materials.
Area of Science:
- Physical Chemistry
- Materials Science
- Chemical Engineering
Background:
- Supercritical fluids are utilized in various industrial processes.
- Phase separation in confined geometries is crucial for separation technologies.
- Understanding fluid behavior under confinement and supercritical conditions is essential.
Purpose of the Study:
- To theoretically investigate capillary-induced phase separation in simple pores under supercritical bulk conditions.
- To explore the role of polymer solvent mixture models in predicting phase behavior.
- To determine if phase separation is dependent on surface transitions.
Main Methods:
- Utilized three distinct polymer solvent mixture models.
- Employed density functional theory for theoretical analysis.
- Analyzed systems under supercritical bulk conditions.
Main Results:
- Demonstrated capillary-induced phase separation in simple pores.
- Showed that phase separation can occur without a pure surface transition.
- Confirmed that demixing is possible even when surface enhancement factors are weak or bulk conditions are supercritical to surface transitions.
Conclusions:
- Capillary-induced phase separation is a viable phenomenon in supercritical conditions within pores.
- This separation mechanism is not solely dependent on surface transitions.
- The findings suggest potential applications in adsorption processes involving porous particles.
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