Charge-dominated phase separation synthesis method of Janus particles with well-defined separated lobes and...

Area of Science:

• Materials Science
• Colloid and Surface Chemistry
• Polymer Chemistry

Background:

• Synthesizing Janus particles (JPs) with controlled architectures and surface chemistries is challenging.
• JPs offer broad applications in science and engineering due to their distinct properties.

Purpose of the Study:

• To develop a novel, scalable method for fabricating Janus particles (JPs) with tunable lobe architectures and surface functionalities.
• To demonstrate precise control over JP morphology and chemistry for advanced material applications.

Main Methods:

• Utilized a phase-separation strategy based on charge-dominated seeded emulsion polymerization.
• Controlled interfacial energy by tuning surface charges of polystyrene (PS) seeds and methacryloxypropyl trimethoxysilane (MPS) emulsions.
• Guided lobe growth using radical polymerization and hydrolysis-condensation reactions.

Main Results:

• Successfully synthesized JPs with multi-scale lobe architectures, including ellipses, dumbbells, and triblock structures.
• Achieved customizable surface chemistries with functional groups like carboxyl, sulfate, and sulfonate.
• Demonstrated selective modification of the polymethacryloxypropyl trimethoxysilane (PMPS) hemisphere for Pickering emulsion applications.

Conclusions:

• The novel method provides a scalable and controllable route for fabricating JPs with programmable architectures and surface chemistries.
• Charge-dominated repulsive forces are key to achieving phase separation and well-defined JP structures.
• This approach enables the creation of JPs suitable for diverse applications, including Pickering emulsions.