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198162 https://hdl.handle.net/2286/R.2.N.198162 http://rightsstatements.org/vocab/InC/1.0/ All Rights Reserved 2024 244 pages Doctoral Dissertation Academic theses Text eng Mithaiwala, Husain Green, Matthew D Dai, Lenore Laura Lind, Mary Perreault, Francois Seo, S. Eileen Arizona State University Partial requirement for: Ph.D., Arizona State University, 2024 Field of study: Chemical Engineering Two of the most pressing challenges humanity faces today are securing access to clean water and addressing plastic waste. These issues have driven academic and industrial researchers to develop innovative solutions using next-generation sustainable technologies. Effectively tackling these complex problems often necessitates a deep understanding of both fundamental and applied research, employing first-principles approach to create effective and lasting solutions. This dissertation explores recent research efforts aimed at addressing these challenges, with a focus on material development, material characterization, and the understanding of structure-property-performance relationships. To address the challenge of desalination, a novel platform has been developed that combines advanced separation techniques with material chemistry to handle saline and hypersaline solutions. This work involves chemical modifications of a hydrophobic polymer backbone with zwitterions, creating a series of zwitterion-modified amphiphilic copolymers: poly(arylene ether sulfone-co-sulfobetaine arylene ether sulfone) [PAES(XX)-co-SBAES(YY)]. These copolymers were synthesized via a polycondensation reaction, followed by post-polymerization modification of the PAES backbone to incorporate sulfobetaine groups. The PAES(XX)-co-SBAES(YY) copolymers were prepared with varying sulfobetaine concentrations (YY = 25, 50, and 75 mol%) and were subsequently converted into standalone, defect-free dense membranes. Characterization techniques were used to assess the hydrophilic properties of these membranes, and their performance in desalination pervaporation were tested to elucidate the structure-property-performance relationship. A key highlight of this study is the synergistic effect of zwitterion chemistry combined with the pervaporation process, prompting a deeper exploration of the fundamental transport properties of salt and water across dense membranes. This understanding is crucial for evaluating their full potential in the desalination space. Next, to tackle the issue of plastic recycling, a simple, cost-effective, and catalyst-free approach is introduced to depolymerize polyester waste i.e., poly(ethylene terephthalate) through aminolysis, yielding bis-alkylterephthalamides (BATAs) using long-chain alkyl amines. This process utilizes a library of primary amines to produce BATAs with tunable alkyl tails, which are then extensively characterized to understand their molecular behavior and material properties. Additionally, this study also explores upcycling strategies to repurpose the synthesized BATA compounds as asphalt compatibilizers and plastic surface modifiers, opening new markets for these materials as value-added products. Chemical Engineering Chemistry Electrospinning Plastic Recycling Polyethylene terepthalate Polysulfone Zwitterions Molecular-Scale Solutions to Macro-Scale Problems: Investigations in Water Treatment and Plastic Upcycling