Cellulose Aerogel Microparticles via Emulsion-Coagulation Technique

Area of Science:

• Materials Science
• Nanotechnology
• Polymer Chemistry

Background:

• Cellulose aerogels are advanced porous materials with tunable properties.
• Controlling the morphology of cellulose aerogels at the microscale is crucial for specific applications.
• Existing methods for producing cellulose aerogels often lack precise control over particle formation.

Purpose of the Study:

• To develop a scalable method for producing cellulose aerogel microparticles.
• To investigate the influence of gelation on microparticle formation and aerogel properties.
• To optimize the nonsolvent induced phase separation process for stable microgel formation.

Main Methods:

• Cellulose was dissolved in a NaOH-based solvent and processed using emulsification with supercritical CO2.
• Nonsolvent induced phase separation was initiated within cellulose droplets in an oil emulsion.
• Coagulation was triggered by nonsolvent diffusion and droplet coalescence for microgel stabilization.

Main Results:

• Cellulose aerogel microparticles with diameters in the tens of microns were successfully synthesized.
• The specific surface area of the aerogel particles ranged from 250 to 350 m²/g.
• Nonsolvent diffusion coupled with coalescence proved most effective for stabilizing microgel shape.

Conclusions:

• The developed method enables the controlled fabrication of cellulose aerogel microparticles.
• Gelation plays a significant role in dictating the final particle characteristics and aerogel properties.
• These microparticles offer potential for applications requiring high surface area materials.