Formulating and Retaining the Structure of Polymerized Surfactant Phases Using a Microemulsion Curvature Framework.

Area of Science:

• Polymer Science
• Materials Science
• Colloid and Surface Chemistry

Background:

• Nanostructured polymers (<100 nm features) have diverse applications in photonics, biomedicine, and environmental science.
• Surfactant-templated polymers offer tunable domain sizes, structures, and compositions, making them highly versatile.
• A gap exists in predicting final polymer structure from industrial-grade polymerizable surfactant formulations.

Purpose of the Study:

• To bridge the gap between surfactant formulation and resultant nanostructured polymer properties.
• To utilize the hydrophilic-lipophilic difference (HLD) and net-average curvature (NAC) frameworks for predictive formulation.
• To correlate microemulsion phase behavior (LLC, L3) with resulting polymer characteristics.

Main Methods:

• Employed the hydrophilic-lipophilic difference (HLD) framework to assess formulation proximity to the phase inversion point (HLD=0).
• Utilized net-average curvature (NAC) to predict interface curvature, micelle/bicontinuous isotropic (L3) system dimensions, and lyotropic liquid crystal (LLC) regions.
• Polymerized fluids from both LLC and L3 microemulsion phases.

Main Results:

• Polymerizing LLC fluids yielded highly swellable nanostructured polymers with LLC structures but low compressive strength.
• Polymerizing L3 fluids produced strong, less water-swellable nanostructured polymers with characteristic lengths matching the parent L3 microemulsion.
• Observed polymer sizes (∼3-8 nm) aligned with HLD-NAC predictions and resulted in translucent materials.

Conclusions:

• HLD-NAC frameworks effectively predict nanostructured polymer formation from surfactant-templated microemulsions.
• Polymerization of LLC phases leads to swellable but mechanically weak materials.
• Polymerization of L3 phases results in robust, less swellable materials with predictable characteristic lengths.