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Solvent-Free Seeded Dispersion Polymerization toward Core-Shell Particles and Microcapsules
Yuan Song1, Ryuga Sakabe1, Shiho Norikane2
1Division of Applied Chemistry, Environmental and Biomedical Engineering, Graduate School of Engineering, Osaka Institute of Technology, 5-16-1, Omiya, Asahi-ku, Osaka 535-8585, Japan.
Langmuir : the ACS Journal of Surfaces and Colloids
|June 2, 2026
Summary
This study introduces a novel solvent-free method to create polymer core/shell particles using salt templates. This technique allows for the formation of unique microcapsules with controllable shell thickness and diverse shapes.
Area of Science:
- Materials Science
- Polymer Chemistry
- Nanotechnology
Background:
- Core/shell particles are synthesized using seeded dispersion/emulsion polymerization.
- This method typically requires liquid media and colloidal stabilizers for stability.
- A need exists for stabilizer-free and solvent-free synthesis methods.
Purpose of the Study:
- To develop a solvent-free seeded dispersion polymerization method without colloidal stabilizers.
- To synthesize polypyrrole (PPy) core/shell particles using sodium chloride (NaCl) templates.
- To demonstrate the versatility of the method using various water-soluble salt templates.
Main Methods:
- Utilized solvent-free oxidative seeded dispersion polymerization of pyrrole (Py) monomer.
- Employed micrometer-sized cubic sodium chloride (NaCl) as seed particles.
- Introduced Py monomer, oxidant, and NaCl seeds into a sealed reactor for vapor-phase polymerization.
Main Results:
- Successfully formed uniform polypyrrole (PPy) shells on NaCl seed particles.
- Achieved controllable PPy shell thickness by adjusting polymerization time.
- Created PPy microcapsules with preserved cubic geometry after NaCl core dissolution.
- Fabricated core/shell particles and microcapsules with various shapes using different salt templates.
Conclusions:
- Developed a versatile, solvent-free, and stabilizer-free method for synthesizing core/shell particles and microcapsules.
- Demonstrated the ability to control shell thickness and particle morphology.
- Showcased the potential for creating shape-tunable microcapsules using various salt templates.
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