Thesis (Ph.D.)--University of Washington, 2021Additive manufacturing (AM) is a rapidly expanding field that has revolutionized a number of diverse fields including medicine, construction, aerospace, and robotics. The hardware of AM has seen a dramatic improvement over the years, and there currently exists a vast array of technologies with unique advantages for different applications. Extrusion-based printers, specifically direct-ink write (DIW), are one such AM technology that has seen extensive use due to its relatively low cost and fast print speeds. Despite the rapid growth of AM, research has mostly focused on the adaptation of existing materials for AM applications- leaving material development lagging behind. This has provided an opportunity for materials scientists and engineers to develop novel materials specifically designed for AM applications. Hydrogels are one class of materials that has garnered significant attention for DIW AM. These soft materials mimic the extracellular matrices of cellular environments and have seen extensive use as cell laden inks for 3D bioprinting. Stimuli-responsive hydrogels respond to environmental cues, enabling both effective printing and providing post-print functionality. This thesis focuses on the development of a multi-stimuli-responsive hydrogel platform based on poly(alkyl glycidyl ether) triblock copolymers. Chapter 1 includes an overview of the field of AM and stimuli-responsive hydrogels for extrusion-based AM. Chapter 2 describes the development of the initial temperature- and shear- responsive triblock copolymer hydrogel platform. Chapter 3 further expands this platform through the photo-chemical crosslinking of the hydrogel network and its implementation for the additive manufacturing of catalytically active living materials (AMCALM). Lastly, Chapter 4 continues to advance the functionality the platform through the addition of thiol-reactive monomers for post-functionalization of the hydrogel material
