Novel additive manufacturing of photocurable ceramic slurry containing freezing vehicle as porogen for hierarchical porous structure

This paper proposes a photocurable ceramic slurry containing a freezing vehicle as a novel feedstock for digital light processing (DLP) technique, which can produce hierarchical porous ceramic structures. A thin layer, comprised of a 3-dimensionally interconnected ceramic/monomer network surrounded by a frozen camphene-camphor alloy network, can be effectively photopolymerized by the DLP process, and thus micropores can be created after the removal of the camphene-camphor network via freeze-drying. Several processing parameters for the DLP process, including the temperature of the building vat, layer thickness, and UV exposure time, were optimized to produce hierarchical porous ceramic structures. The effect of freezing vehicle content on the microporous structures (e.g., porosity and pore size) and mechanical properties of ceramic frameworks was examined. In addition, hierarchical macro/micro-porous ceramic scaffolds comprised of microporous ceramic frameworks separated by microporous CaP frameworks were produced, and their porous structures and mechanical properties were characterized.