Date of Award

8-2025

Degree Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

School

Polymer Science and Engineering

Committee Chair

Dr. Zhe Qiang

Committee Chair School

Polymer Science and Engineering

Committee Member 2

Dr. Derek Patton

Committee Member 2 School

Polymer Science and Engineering

Committee Member 3

Dr. Sarah Morgan

Committee Member 3 School

Polymer Science and Engineering

Committee Member 4

Dr. Xiaodan Gu

Committee Member 4 School

Polymer Science and Engineering

Committee Member 5

Dr. Olivia McNair

Committee Member 5 School

Polymer Science and Engineering

Abstract

Polyolefins are extremely ubiquitous materials due to their satisfactory material properties, ease of synthesis, and low cost. Unfortunately, their extensive use has led to a global plastic waste mismanagement problem. As such, notable efforts have recently focused on converting these commodity polymers into vitrimers, or dynamic networks, to extend their use-life and tailor their properties. However, the fundamental polymer physics of these emerging materials, remain largely underexplored, hindering their widespread implementation. To address this challenge and enable a more sustainable future, the overarching goal of my dissertation research is to understand the fundamental structure-property relationships within complex polyolefin-derived vitrimer systems. This work first focuses on toughening extremely brittle, low molecular weight commodity polypropylene through conversion into vitrimers with polymeric, poly(ethylene glycol)-based crosslinkers in order to create model opportunities for otherwise landfill-bound plastics. From there, the potential for tailorable mechanical properties through crosslinkers of different identities and characteristics within dynamic networks was realized and extended into commodity polyethylene systems. The composition-structure-property relationships of PE-vitrimers crosslinked with 8-arm polyhedral oligomeric silsesquioxane nanoparticles (NPs) were investigated and it was determined that the use of NP crosslinkers can modulate the properties of polyolefin-derived semicrystalline vitrimer materials. Moreover, I investigated the nanoconfinement impact on the physical properties of an emerging polyolefin system, specifically atactic, cis poly(methylene-1,3-cyclohexane). Molecular packing behaviors and their impact on bulk material properties were examined by analyzing the glass transition temperature and dynamic fragility under thin film confinement. Finally, the last sections of this dissertation explore the importance of polymer sustainability education for the next generation, where labs for immiscible polymer compatibilization and community outreach through coastal and local plastic waste cleanups were designed and effectively implemented.

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