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Recently, the manufacturing of porous polydimethylsiloxane (PDMS) with engineered porosity has gained considerable interest due to its tunable material properties and diverse applications. An innovative approach to control the porosity of PDMS is to use transient liquid phase water to improve its mechanical properties, which has been explored in this work. Adjusting the ratios of deionized water to the PDMS precursor during blending and subsequent curing processes allows for controlled porosity, yielding water emulsion foam with tailored properties. The PDMS-to-water weight ratios were engineered ranging from 100:0 to 10:90, with the 65:35 specimen exhibiting the best mechanical properties with a Young’s Modulus of 1.17 MPa, energy absorption of 0.33 MPa, and compressive strength of 3.50 MPa. This led to a porous sample exhibiting a 31.46% increase in the modulus of elasticity over a bulk PDMS sample. Dowsil SE 1700 was then added, improving the storage capabilities of the precursor. The optimal storage temperature was probed, with −60 °C resulting in great pore stability throughout a three-week duration. The possibility of using these water emulsion foams for paste extrusion additive manufacturing (AM) was also analyzed by implementing a rheological modifier, fumed silica. Fumed silica’s impact on viscosity was examined, revealing that 9 wt% of silica demonstrates optimal rheological behaviors for AM, bearing a viscosity of 10,290 Pa·s while demonstrating shear-thinning and thixotropic behavior. This study suggests that water can be used as pore-formers for PDMS in conjunction with AM to produce engineered materials and structures for aerospace, medical, and defense industries as sensors, microfluidic devices, and lightweight structures. 

Abstract This study explores the potential of single crystal barium titanate (BTO) platelets to fabricate nontoxic ceramics with enhanced material properties through texturization of grain structure. The proposed methodology relies on direct ink write additive manufacturing to enable grain‐oriented growth of BTO ceramics by utilizing a combination of spherical and platelet‐shaped particles. The use of platelet‐shaped particles in the ceramic ink guides particle alignment parallel to the build plate due to shear forces at the nozzle during the printing process. While platelet contents ranging from 0 to 40 wt.% showed a decrease in density as the content increased, experimental data revealed an incremental trend between platelet content, dielectric properties, and the degree of alignment of the particles on the F200 crystal plane, achieving a maximum texturized orientation of 65%. Such orientation resulted in 29.55% improved dielectric properties compared with randomly oriented BTO ceramic. The findings of this research validate the effectiveness of additive manufacturing technologies to tailor the microstructural characteristics of ceramics for specific functional applications.