Patent ID: 8466206

Claim:
A process for forming polymer particles with aligned pores and controlled narrow particle size distribution, comprising: a) forming an oil phase by dissolving a polymeric binder in a solvent; b) dispersing the oil phase into a water phase containing a controlled amount of particulate stabilizer and forming an oil-in-water emulsion of controlled narrow dispersed oil phase droplet size distribution; c) freezing the emulsion to freeze solvent in the oil droplets to form frozen solvent domains within the polymeric binder, and also the water in the continuous water phase; and d) removing the frozen solvent from the polymeric binder and the frozen water in the continuous water phase, thereby forming porous polymer particles of controlled narrow particle size distribution and containing directional aligned non-spherical pore structures, wherein the formed porous particles have a volume based particle size geometric standard deviation of less than 1.5 for particle size of the particles measured in equivalent circular diameter.