Additive Manufacturing of 3D Functional Materials: From Surface Chemistry to Combustion-Derived Materials

Citation

Yee, Daryl Wei Liang (2020) Additive Manufacturing of 3D Functional Materials: From Surface Chemistry to Combustion-Derived Materials. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/ya58-cn88. https://resolver.caltech.edu/CaltechTHESIS:06042020-112316408

Abstract

Over the past decade, additive manufacturing has emerged as one of the most powerful manufacturing tools available today. Vat photopolymerization techniques, in particular, are especially promising as they are capable of achieving high resolutions and throughputs. However, the vast majority of materials that are compatible with them only have structural functionality. The fabrication of functional materials still remains a challenge in the field: functional polymers often require a complex multi-step synthesis. Ceramics-based photoresins are limited in composition and are challenging to use or synthesize. Metals have also been hardly explored with vat photopolymerization techniques.

This thesis explores methods of fabricating functional materials with vat photopolymerization. We develop accessible techniques for the fabrication of functional polymers, ceramics, metals, and multimaterials at a variety of length scales, from sub-micron to centimeter scales. On the polymer front, we first explore how surface coatings can be an accessible method of introducing chemical functionality to a material. In particular, we demonstrate the surface coating of genomic DNA on an architected polymeric structure and show how it can be used as a drug capture device to reduce off-target toxicity in chemotherapy. We also explore the use of click chemistry, the thiol-Michael reaction in particular, in the facile synthesis of acrylate monomers with a variety of functional groups. We demonstrate the compatibility of these functionalized monomers with two-photon lithography and highlight some potential applications of these functional polymers structures.

In the fabrication of ceramics and metals, we present a novel technique called photopolymer complex synthesis that combines solution combustion synthesis with vat photopolymerization to enable their fabrication. We illustrate the use of this technique by first fabricating piezoelectric zinc oxide architected structures with sub-micron features using two-photon lithography. Following that, we fabricate lithium cobalt oxide structures using digital light processing printing and highlight their use as architected lithium-ion battery cathodes. Lastly, we show how photopolymer complex synthesis can be expanded to fabricate metal and multimaterial architected structures. Our work highlights the use of polymer chemistry and materials science in expanding the range of materials that are compatible with vat photopolymerization, with the vision of democratizing the fabrication of advanced functional materials and enabling the production of previously impossible 3D devices.

Thesis Files