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In this article, the processing and microstructures of porous mullite bodies prepared by modifying the conventional route of the starch consolidation casting method were studied. The proposed route, called the "soluble route", involves the use of native starches (i.e., potato, cassava, and corn starches) and a synthesized granular cold-water-soluble (GCWS) starch. Stable aqueous mullite-starch suspensions (0.25 starch volume fraction of 40 vol% total solids) were prepared by mixing. The total starch content was a mixture of ungelatinized native starch and GCWS starch with a 1:10 ratio of GCWS starch to total starch. Steady-state shear flow properties of the suspensions were analyzed by measuring viscosity. The addition of CGWS starch increased the starting suspension viscosity and thus prevented the particle segregation. Porous mullite bodies were obtained by heating (80°C, 2 h) the suspensions in metallic molds and by drying (40°C, 24 h) and sintering (1650°C, 2 h) the green disks after burning out the starch (650°C, 2 h). Green bodies obtained before and after the burning-out process, and the sintered disks were characterized with density and porosity measurements (Archimedes method) and microstructural analysis by scanning electron microscopy. The phases generated after the sintering process were determined by X-ray diffraction analysis, and pore size distributions were studied by Hg-porosimetry. The obtained results showed that the use of the GCWS starch made the shaping of homogeneous mullite bodies without cracks or deformations possible along with the development of controlled porous microstructures.

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Tissue engineering requires highly porous complex structures with interconnected pores and tightly controlled pore sizes, added to customized production. Additive manufacturing (AM) is nowadays one of the most suitable technologies for the preparation of structures with strictly defined complex three‐dimensional architectures. Moreover, computed tomography and magnetic resonance imaging can be employed to obtain personalized medical devices. Fused deposition modeling (FDM) is one of the most common, easiest, and cost‐effective AM techniques to obtain 3D objects from a wide variety of materials. However, there is a lack of bioresorbable materials that can fit the increasing demand for biomedical applications requiring stiff elastomers. In this work, a series of bioresorbable segmented poly(ester urethanes) (SPEU) with high hard segment content was synthesized and physicochemically characterized. The materials with higher thermal stability were processed into homogeneous filaments by hot‐melt extrusion with no need for additives nor plasticizers. These filaments were evaluated for FDM, and structures with controlled porosity, filament diameter, and in‐plane pore size could be easily obtained by modifying the printing parameters. Regarding SPEU mechanical properties, the obtained scaffolds could be promising for cartilage tissue engineering applications.

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