3D Surface Functionalization of Emulsion-Templated Polymeric Foams

We describe the preparation of porous polymeric scaffolds via polymerization of the oil phase in high internal phase water-in-oil-emulsions using amphiphilic block copolymers polystyrene-b-poly(ethylene oxide), polystyrene-b-poly(acrylic acid), poly(1,4-butadiene)-b-poly(ethylene oxide), and poly(1,4-butadiene)-b-poly(acrylic acid) as surfactants. We show that the block copolymers anchor to the polymerized oil phase via the lipophilic block, which can occur by chemical and/or physical entanglement and consequent presentation of the hydrophilic block on the pore surfaces. The in situ polymerization enables the full surface functionalization of the porous materials with the final surface chemistry dictated by the hydrophilic block. Furthermore, the foam physical architecture may be tailored through controlling emulsion parameters such as the initiator, shear rate, and aqueous phase volume fraction.