Silicone oil emulsions stabilized by semi-solid nanostructures entrapped at the interface

Area of Science:

• Materials Science
• Colloid and Surface Chemistry

Background:

• Traditional oil-in-water emulsions use water-soluble surfactants, which are prone to degradation under stress.
• The mobility of conventional surfactants limits emulsion stability against physical and chemical challenges.

Purpose of the Study:

• To develop a new strategy for preparing highly stable silicone oil-in-water emulsions.
• To utilize a water-insoluble amphiphilic block copolymer for enhanced emulsion structural integrity.

Main Methods:

• Dissolving poly(ethylene oxide)-b-poly(epsilon-caprolactone) (PEO-b-PCL) in silicone oil above PCL's melting point.
• Dispersing the polymer/oil mixture in water to induce irreversible reorganization of PEO-b-PCL into solid interfacial nanostructures.

Main Results:

• The PEO-b-PCL nanostructures formed a robust physical barrier, preventing emulsion coarsening.
• The resulting silicone oil emulsions demonstrated exceptional stability against variations in pH, ionic strength, and temperature.

Conclusions:

• Amphiphilic block copolymers offer a superior approach to stabilizing oil-in-water emulsions compared to traditional surfactants.
• The developed method yields emulsions with remarkable resilience, suitable for demanding applications.