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Polyelectrolytes adsorbed at water-water interfaces
R Hans Tromp1, Remco Tuinier2, Mark Vis3
1NIZO food research, Kernhemseweg 2, 6718 ZB Ede, The Netherlands and Van 't Hoff Laboratory for Physical and Colloid Chemistry, Department of Chemistry, Debye Institute for Nanomaterials Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
Physical Chemistry Chemical Physics : PCCP
|November 8, 2016
Summary
Polyelectrolytes strongly adsorb at water-water interfaces, forming complexes that stabilize water-in-water emulsions. This interfacial complexation persists even in high salt concentrations.
Area of Science:
- Polymer Science
- Colloid and Surface Science
- Materials Chemistry
Background:
- Polyelectrolytes exhibit significant adsorption at water-water interfaces.
- Phase separation of polymers in aqueous solutions creates these interfaces.
- Understanding interfacial behavior is crucial for emulsion stabilization.
Purpose of the Study:
- To investigate polyelectrolyte adsorption at water-water interfaces.
- To explore the mechanism of interfacial accumulation.
- To assess the potential for stabilizing water-in-water emulsions.
Main Methods:
- Utilized a model system of neutral polymer A and charged polymer B.
- Introduced a polyelectrolyte with composition similar to polymer A and opposite charge to polymer B.
- Observed interfacial accumulation and measured interfacial tension under varying salt concentrations.
Main Results:
- Demonstrated strong interfacial accumulation of the added polyelectrolyte.
- Hypothesized accumulation is due to interfacial complexation.
- Observed persistent adsorption even at high salt concentrations.
- Noted a limited effect on interfacial tension.
Conclusions:
- Polyelectrolytes can form complexes at water-water interfaces.
- This phenomenon offers a novel route for stabilizing water-in-water emulsions.
- Interfacial complexation is robust and effective under various conditions.
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