Modeling for nanoparticle-stabilized, robust small-domain bicontinuous emulsions

Area of Science:

• Materials Science
• Chemical Engineering
• Colloid Science

Background:

• Bicontinuous emulsion gels are promising for interfacial microreactors due to large interfacial areas.
• Structural stability, balancing small domain sizes with mechanical strength, is a key challenge.
• Existing surfactants face trade-offs between interfacial energy reduction and domain size minimization.

Purpose of the Study:

• To compare the structural evolution and properties of bicontinuous emulsion gels formed by two distinct surfactant systems.
• To evaluate the suitability of nanoparticle-polymer (NP-PL) surfactants versus Janus nanoparticle (Janus NP) surfactants for microreactor applications.
• To identify strategies for optimizing gel stability and performance in microreactors.

Main Methods:

• Coarse-grained molecular dynamics simulations were employed to model and analyze gel structures.
• Two surfactant systems were investigated: in situ-formed NP-PL surfactants and Janus NPs.
• Gel properties, including domain size, structural evolution, and stability, were compared.

Main Results:

• Both NP-PL surfactants and Janus NPs enabled small domain sizes (approximately 200 nm), reducible with increased concentration.
• Some Janus NPs formed non-contributory micelle-like structures, impacting network formation.
• NP-PL surfactants resulted in gels with superior thermal and kinetic stability compared to Janus NPs.

Conclusions:

• NP-PL surfactants provide a more robust and stable platform for bicontinuous emulsion gels in microreactor applications.
• Understanding surfactant-specific structural pathways is crucial for designing stable, high-performance microreactors.
• This research offers insights into optimizing emulsion gel design for enhanced interfacial reaction engineering.