Roughly Spherical: Tailored PMMA-SiO₂ Composite Supraparticles with Optimized Powder Flowability for Additive...

Area of Science:

• Materials Science
• Polymer Science
• Additive Manufacturing

Background:

• Particulate materials with engineered properties are vital for daily life.
• Polymer powders with high flowability are crucial for powder-based additive manufacturing (AM).
• Current material selection for powder-based AM is limited.

Purpose of the Study:

• To design spherical polymethyl methacrylate (PMMA) and PMMA-SiO2 composite supraparticle powders.
• To achieve excellent powder flowability and tailored composition for powder-based AM.
• To establish process-structure-property relationships for supraparticle design.

Main Methods:

• Bottom-up assembly of supraparticle powders using colloidal primary particles.
• Control over surface roughness and internal morphology via primary particle selection.
• Spray-drying techniques to control external parameters and primary particle sizes.

Main Results:

• Demonstrated precise control over supraparticle surface roughness and internal morphology.
• Established correlations between process parameters, structure, and macroscopic powder properties (flowability, bed density).
• Successfully applied PMMA and PMMA-SiO2 composite supraparticles in powder bed AM, producing defect-free, two-layered specimens.

Conclusions:

• Engineered supraparticle powders exhibit excellent flowability and tunable composition.
• The developed process allows for controlled synthesis of advanced polymer composite powders for AM.
• The optimized composite powders enable layer fusion and uniform additive distribution without flow aids.