ONE-STEP SYNTHESIS OF SPHERICAL/NONSPHERICAL POLYMERIC PARTICLES USING NON-EQUILIBRIUM MICROFLUIDIC DROPLETS

摘要

A simple but highly versatile microfluidic system is presented to synthesize monodisperse polymeric particles, without necessitating polymerization processes. The principle utilizes the non-equilibrium oil-in-water (o/w) droplets, of which the dispersed phase was composed of a water-soluble organic solvent and water-insoluble polymer molecules. The non-equilibrium droplets, temporary formed at the microchannel confluence, is gradually diminished as the solvent is dissolved into the continuous water phase, while the polymer molecules are precipitated and solid particles are finally formed. We successfully synthesized polymer (polystyrene and poly(methyl methacrylate)) particles with sizes much smaller than the initial droplet size, and found that the polymer concentration and the molecular weight are the critical factors dominating the spherical/nonspherical particle morphologies.