Porous polymeric materials by 3D printing of photocurable resin
Porous polymeric materials have a wide range of applications, including as tissue scaffolds, catalyst supports, and membrane filters. This paper presents a new fabrication method to prepare components of porous materials by combining 3D printing with salt leaching. Sacrificial salt particulates and photocurable resin are mixed and used as the ink. 3D objects are then printed in a customized digital light processing printer. Owing to the interconnection of salt particles in the objects, porous polymeric components can be obtained upon salt leaching. Multiple pore sizes can be achieved by using selectively sieved salt powders in the ink formula. This method is very simple to implement for different photocurable resins to create 3D porous objects with complicated shapes. It has the advantage of being self-supporting and can be used to print hollow components, especially parts exhibiting the Droste effect. Shape memory foams by using shape memory polymers and dual-pore scaffolds can also be 3D printed with potential applications in tissue engineering. In addition, the porous components can be used as a template for embedding a conductive material to obtain 3D printed objects that function as flexible conductive components or filling with a second polymer to obtain a composite with a tunable modulus.