Nonaqueous Emulsion Polycondensation Enabled by a Self-Assembled Cage-like Surfactant

Area of Science:

• Supramolecular Chemistry
• Materials Science
• Colloid and Surface Chemistry

Background:

• Nonaqueous emulsions are vital for water-sensitive applications like controlled polymerizations and stabilizing hydrolyzable reagents.
• Stabilizing these emulsions requires specialized molecular surfactants, which are currently scarce.

Purpose of the Study:

• To introduce a novel molecular surfactant for stabilizing oil-in-oil emulsions.
• To demonstrate its utility in templating microstructured polymer synthesis.
• To investigate its host-guest chemistry and behavior in aqueous media.

Main Methods:

• Self-assembly of a coordination cage functionalized with cholesterol moieties.
• Utilizing the cage as an amphiphile to stabilize emulsions of immiscible organic solvents.
• Employing emulsion droplets as templates for polycondensation reactions to synthesize polyurethanes and polyureas.
• Investigating host-guest complex formation and aqueous aggregation behavior.

Main Results:

• A cholesterol-decorated coordination cage was successfully synthesized and demonstrated to act as a molecular surfactant for oil-in-oil emulsions.
• The cage facilitated the templated synthesis of microstructured polyurethane and polyurea materials with controlled particle sizes and morphologies.
• The amphiphilic cage showed potential for encapsulating guest molecules, forming functional host-guest assemblies that also act as surfactants.
• The aggregation behavior of the cage in aqueous solutions was also characterized.

Conclusions:

• The developed coordination cage-based amphiphile offers a new solution for stabilizing nonaqueous emulsions.
• This surfactant enables the creation of advanced microstructured materials through templated polymerization.
• The findings expand the toolkit for designing functional supramolecular systems for diverse applications.