Interfacial composition and structural parameters of water/C12-s-C12 x 2Br/n-hexanol/n-heptane microemulsions studied...

Area of Science:

• Colloid and Surface Chemistry
• Physical Chemistry
• Materials Science

Background:

• Microemulsions are thermodynamically stable systems crucial for solubilizing various substances.
• Understanding interfacial composition is key to controlling microemulsion properties and applications.
• Gemini surfactants offer unique advantages in microemulsion formulation due to their structure.

Purpose of the Study:

• To investigate the interfacial composition of water/C12-s-C12 x 2Br/n-hexanol/n-heptane microemulsions.
• To determine the influence of water content and gemini surfactant spacer length on interfacial behavior.
• To estimate structural parameters, including water pool radius, and compare with conventional surfactants.

Main Methods:

• Detailed study of interfacial composition using the dilution method.
• Analysis of structural parameters through dilution experiment data.
• Estimation of water pool radius and its variation with water content (W0).

Main Results:

• n-Hexanol population on droplet surfaces peaked with increasing water content.
• Decreased n-hexanol population with increased spacer length in C12-s-C12 x 2Br.
• Water pool radius showed high sensitivity to water content, varying from 0.74 to 5.35 nm.
• C12-2-C12 x 2Br facilitated larger droplet formation compared to conventional surfactants (CPC, CTAB).

Conclusions:

• The interfacial composition of microemulsions is significantly affected by water content and surfactant structure.
• Gemini surfactant C12-2-C12 x 2Br promotes the formation of larger water pools.
• These findings suggest C12-2-C12 x 2Br-based microemulsions are effective for solubilizing substantial amounts of water.