| Project Detail |
Nature has optimized the properties of its building blocks by spatially varying hierarchical microstructures within complex form factors. Additive manufacturing techniques, in particular direct ink writing (DIW), are promising pathways towards replicating these systems synthetically, leading to printed materials with tarilored materials properties. However, current DIW techniques do not offer access to out-of-equilibrium materials, greatly limiting printable microstructures. To overcome this limitation, a new DIW technique, termed FloR3D, will be developed in this project. By integrating an evolving chemical reaction into the printing process itself, this Flow-Reactor coupled 3D printing technique allows for out-of-equilibrium microstructures to be generated within the nozzle, which is subsequently trapped upon deposition. Through on-the-fly variations of the relative flow rates into the flow reactor, FloR3D will allow for voxel-level control of the material composition and microstructure, resulting in optimized and spatially-varied hierarchical structures. By incorporating a polymerization-induced microphase separation (PIMS) process, spinodally-decomposed bicontinuous microstructures, which was previously unachievable by DIW, will be printed. Printing these bicontinuous systems, commonly used in nature to exhibit structural coloration, will result in angular-independent structural colored materials with arbitrary form factor. Furthermore, by including photoresponsive monomers within the PIMS system and an in-situ UV source, the materials refractive indices can be tuned independently of the microstructural feature size, resulting in materials with gradient and spatially-patterned optical properties. Ultimately, beyond the complex photonic materials produced in this proposal, the design of FloR3D can be broadened to incorporate a variety of other chemical reactions, leading to a new pathway towards free-form high-performance materials. |
