Orthogonal Photochemistries for Multimaterial 3D Printing
Light-mediated 3D printing has gained significant interest due to the inherent advantages of light as external stimuli, including spatiotemporal control, easy access, and ability to enact orthogonal chemical reactions. Concurrently, there is an increased demand for novel chemistries that enable easy set up and the synthesis of a variety of materials. As 3D printing processes require a rapid polymerization for practical applications, free radical or cationic polymerization methods are traditionally used. However, these polymerization reactions are highly exothermic, lead to immobilization of unreacted radical species within the network, resulting in mechanically weak structures, and are limited to the production of materials with properties that cannot be altered post-printing. Materials with mutable properties are useful as they can be recycled and repurposed for different applications. The high chain-end fidelity of polymers synthesized via controlled radical polymerization (CRP) methods allows polymer networks to be reactivated and modified via post-functionalization. Despite many benefits of CRP techniques, slow polymerization rates and the general requirement for deoxygenation such as inert gas sparging have placed significant limitations.
To exploit the potential of living multimaterial 3D printing, this proposal will explore different strategies to improve the polymerization rate and the limitations of CRP and controlled cationic polymerization chemistries.
