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Adsorption of the Three-phase Emulsion on Various Solid Surfaces.
Yasutaka Enomoto1, Yoko Imai2, Kazuo Tajima2
1Graduate School of Applied Chemistry, Kanagawa University.
Journal of Oleo Science
|June 20, 2017
Summary
This study shows that cationic three-phase emulsions adsorb onto solid surfaces, maintaining structure. This adsorption, driven by van der Waals forces, reaches high surface coverage, offering new possibilities for emulsion applications.
Area of Science:
- Colloid and Surface Science
- Materials Science
- Physical Chemistry
Background:
- Three-phase emulsions utilize vesicles as emulsifiers, forming an independent phase distinct from conventional surfactant-stabilized emulsions.
- Vesicle-stabilized emulsions are expected to adsorb onto solid/water interfaces due to their unique structure.
- Cationic emulsions were developed to enhance adsorption onto negatively charged solid substrates.
Purpose of the Study:
- To investigate the adsorption behavior of three-phase emulsions on various solid substrates.
- To determine the factors influencing emulsion adsorption and surface coverage.
- To elucidate the mechanism behind the irreversible adhesion of emulsions to surfaces.
Main Methods:
- Preparation of a cationic three-phase emulsion using polyoxyethylene-(10) hydrogenated castor oil and cetyltrimethylammonium bromide.
- Adsorption experiments involving dipping silicon, glass, and copper substrates into the emulsion.
- Quantification of adsorbed hexadecane using gas chromatography.
- Investigation of adsorption on various solid surfaces.
Main Results:
- The cationic three-phase emulsion successfully adsorbed onto silicon, glass, and copper substrates while preserving its structure.
- Adsorbed hexadecane quantity increased with emulsion concentration, plateauing similarly to molecular adsorption.
- Maximum surface coverage achieved was approximately 80%.
- Even nonionic three-phase emulsions demonstrated adsorption, indicating a broader applicability.
Conclusions:
- Three-phase emulsions exhibit significant adsorption onto diverse solid surfaces.
- Adsorption is influenced by emulsion composition and concentration, reaching high surface coverage.
- Irreversible adhesion is facilitated by van der Waals attractive forces, a novel mechanism for emulsion adsorption.
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