Thesis advisor: Jeffery A. Byers / This dissertation discusses the development of catalytic systems within the context of polymer synthesis and functionalization towards the fulfillment of circular plastic economy. Chapter 1 provides an overview of the limitations of the current mechanical recycling for plastic disposal and two general ways to improve the current system by chemical strategies. Chapter 2 discusses the development of a chemically recyclable thermoplastic elastomer derived from relatively cheap feedstock using redox-switchable polymerization. Chapter 3 describes the application of C-H activation and cross-coupling strategy on commodity polyolefins and the effect on the polymer physiochemical properties by the introduction of functional groups, which has the potential to serve in polymer upcycling. Chapter 4 describes the dehydrogenation of polyethylene (PE) and polypropylene (PP) along with further functionalization of the unsaturated product to demonstrate a route of synthesizing PE/PP compatibilizers from plastic waste. Chapter 5 summarizes our development of simulation-based methods to obtain kinetic information of transition-metal catalyzed copolymerization that may include reversible propagation. / Thesis (PhD) — Boston College, 2024. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

Master thesis is focusing on possibility of recycling waste from 3D prints. Goal was to degin a make lament extruder and winder. Design is based on research of avaible comercial and OpenSource solutions. The result is working machine with compact oor prejction, which is able to produce 110 grams of lament per hour. Deviation from diameter was ±0, 07. Conclusion place great emphasis on further improving and testing, beacuse it has not been reached limits of machine.