Related Experiment Video
Updated: Mar 30, 2026
09:47
Facile Preparation of Internally Self-assembled Lipid Particles Stabilized by Carbon Nanotubes
Published on: February 19, 2016
10.2K
Oil-in-oil emulsions stabilised solely by solid particles.
Bernard P Binks1, Andrew T Tyowua
1Department of Chemistry, University of Hull, Hull HU6 7RX, UK. b.p.binks@hull.ac.uk.
Soft Matter
|November 10, 2015
Summary
This study demonstrates that hydrophobic particles effectively stabilize emulsions of vegetable and silicone oils. Particle hydrophobicity controls emulsion type, with stable emulsions forming near phase inversion.
Area of Science:
- Colloid and Surface Science
- Materials Science
- Emulsion Technology
Background:
- Emulsions of immiscible oils require effective stabilization to prevent separation.
- Particle stabilizers offer an alternative to traditional surfactants for emulsion formulation.
Purpose of the Study:
- To investigate the use of surface-modified fumed silica particles as sole stabilizers for vegetable oil-silicone oil emulsions.
- To explore the influence of particle hydrophobicity, oil viscosity, and particle characteristics on emulsion type and stability.
- To demonstrate the preparation of stable multiple emulsions and induce phase inversion.
Main Methods:
- Utilizing fumed silica particles coated with hydrocarbon or fluorocarbon groups.
- Formulating emulsions with various vegetable oils and linear polydimethylsiloxane (PDMS) oils of differing viscosities.
- Investigating transitional and catastrophic phase inversion by adjusting particle hydrophobicity and oil volume fractions.
- Calculating particle contact angles at the oil-oil interface to predict emulsion type.
- Extending the study to various particle types (clay, zinc oxide, silicone, calcium carbonate) with differing properties.
Main Results:
- Transitional phase inversion from silicone-in-vegetable (S/V) to vegetable-in-silicone (V/S) emulsions was observed with increasing particle hydrophobicity.
- Emulsions near inversion demonstrated stability against coalescence and separation for over a year.
- Stable S/V emulsions could be formed with relatively hydrophilic particles by increasing silicone oil viscosity.
- Calculated contact angles, including a small polar contribution from oils, accurately predicted emulsion types.
- Stable V/S/V multiple emulsions were successfully prepared using a two-step procedure with particles of differing hydrophobicity.
- Catastrophic phase inversion from V/S to S/V was achieved by increasing vegetable oil fraction.
- Hydrophobic particles such as clay, zinc oxide, silicone, and calcium carbonate were found to be efficient V/S emulsion stabilizers.
Conclusions:
- Particle hydrophobicity is a critical parameter dictating the type and stability of oil-in-oil emulsions.
- Surface-modified silica particles are versatile stabilizers for various emulsion systems.
- Understanding interfacial properties through contact angle measurements aids in predicting emulsion behavior.
- The findings provide a pathway for designing stable emulsions and controlling phase behavior through particle engineering.
Related Concept Videos
03:22Colloids
22.1K
Children at play often make suspensions such as mixtures of mud and water, flour and water, or a suspension of solid pigments in water known as tempera paint. These suspensions are heterogeneous mixtures composed of relatively large particles that are visible to the naked eye or can be seen with a magnifying glass. They are cloudy, and the suspended particles settle out after mixing. On the other hand, a solution is a homogeneous mixture in which no settling occurs and in which the dissolved...
22.1K
01:29The Colloidal State
142
The formation of a colloidal system is exemplified by an aqueous solution containing Cl− ions is introduced to another containing Ag+ ions, resulting in the precipitation of solid AgCl as extremely tiny crystals. Instead of settling out as a filterable precipitate, these crystals remain suspended in the liquid, showcasing a colloidal system.A colloidal system involves colloidal particles within the approximate range of 1 to 1000 nm in at least one dimension, dispersed in a medium called...
142
03:00Solubility
22.8K
Solution, Solubility, and Solubility Equilibrium
A solution is a homogeneous mixture composed of a solvent, the major component, and a solute, the minor component. The physical state of a solution—solid, liquid, or gas—is typically the same as that of the solvent. Solute concentrations are often described with qualitative terms such as dilute (of relatively low concentration) and concentrated (of relatively high concentration).
In a solution, the solute particles (molecules,...
A solution is a homogeneous mixture composed of a solvent, the major component, and a solute, the minor component. The physical state of a solution—solid, liquid, or gas—is typically the same as that of the solvent. Solute concentrations are often described with qualitative terms such as dilute (of relatively low concentration) and concentrated (of relatively high concentration).
In a solution, the solute particles (molecules,...
22.8K
01:09Colloidal precipitates
6.8K
The high insolubility of some precipitates can result in an unfavorable relative supersaturation. This can lead to colloidal particles with a large surface-to-mass ratio, where adsorption is promoted. For instance, in the precipitation of silver chloride, silver ions are adsorbed on the surface of the colloidal particles, forming a primary layer. This layer attracts ions of opposite charge (such as nitrate ions), forming a diffuse secondary layer of adsorbed ions. This electric double layer...
6.8K