Uniform Microparticles with Controllable Highly-Interconnected Hierarchical Porous Structures

  A simple and versatile strategy is developed for one-step fabrication of uniform polymeric microparticles with controllable highly-interconnected hierarchical porous structures.  Monodisperse water-in-oil-in-water (W/O/W) emulsions, with methyl methacrylate, ethylene glycol dimethacrylate and glycidyl methacrylate as the monomer-containing oil phase, are generated from microfluidics and used for constructing the microparticles.  Due to the partially miscible property of oil/aqueous phases, the monodisperse W/O/W emulsions can deform into desired shapes depending on the packing structure of inner aqueous microdrops, and form aqueous nanodrops in the oil phase.  The deformed W/O/W emulsions allow template syntheses of highly-interconnected hierarchical porous microparticles with precisely and individually controlled pore size, porosity, functionality, and particle shape.  The microparticles elaborately combine the advantages of enhanced mass transfer, large functional surface area, and flexibly tunable functionalities, providing an efficient strategy to physically and chemically achieve enhanced synergetic performances for extensive applications.  This is demonstrated by using the microparticles for oil removal for water purification and protein adsorption for bio-separation.  The method proposed in this study provides full versatility for fabrication of functional polymeric microparticles with controllable hierarchical porous structures for enhancing and even broadening their applications.