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Mixed O/W emulsions stabilized by solid particles: a model system for controlled mass transfer triggered by
Audrey Drelich1, Jean-Louis Grossiord, François Gomez
1EA 4297 Transformations Intégrées de la Matière Renouvelable UTC/ESCOM, Université de Technologie de Compiègne, Compiègne, France.
Journal of Colloid and Interface Science
|August 23, 2012
Summary
This study developed a novel oil-in-water emulsion system using silica particles instead of surfactants. Adding surfactants above their critical micellar concentration triggered oil transfer between droplets via micellar transport.
Area of Science:
- Colloid and Surface Science
- Materials Science
- Chemical Engineering
Background:
- Traditional oil-in-water (O/W) emulsions rely on surfactants for stabilization.
- Investigating mass transfer in emulsions requires controlled systems to isolate variables.
- Understanding surfactant roles in emulsion dynamics is crucial for various applications.
Purpose of the Study:
- To develop a model O/W emulsion system stabilized by silica particles, enabling surfactant-free formulation.
- To investigate the specific effects of different surfactants and their concentrations on inter-droplet mass transfer.
- To elucidate the mechanism of oil transfer in mixed emulsions.
Main Methods:
- Formulation of O/W emulsions using a mixture of hydrophilic/hydrophobic silica particles as stabilizers.
- Addition of various surfactants post-emulsification to study their impact on mass transfer.
- Monitoring oil transfer between hexadecane and tetradecane droplets using differential scanning calorimetry (DSC).
Main Results:
- Successful creation of surfactant-free O/W emulsions stabilized by silica particles.
- Demonstration that surfactants, at concentrations above their critical micellar concentration (CMC), can induce oil transfer.
- Identification of micellar transport as the mechanism responsible for tetradecane transfer to hexadecane droplets.
Conclusions:
- Silica particles offer a viable alternative to surfactants for O/W emulsion stabilization.
- Surfactants play a critical role in mediating mass transfer in emulsions through mechanisms like micellar transport.
- The developed model system provides a platform for detailed studies on surfactant-driven mass transfer in emulsions.
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