Date of Award
12-2025
Degree Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
School
Polymer Science and Engineering
Committee Chair
Dr. Derek Patton
Committee Chair School
Polymer Science and Engineering
Committee Member 2
Dr. Boran Ma
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. Sergei Nazarenko
Committee Member 4 School
Polymer Science and Engineering
Committee Member 5
Dr. Jeffrey Wiggins
Committee Member 5 School
Polymer Science and Engineering
Abstract
Increased interest in building a circular plastics economy has stimulated research into reprocessable thermoset materials that retain thermomechanical properties upon reprocessing. Epoxy-amines are a common class of thermoset material widely used in fiber-reinforced composites, aerospace, and coatings. The presence of interchain hydrogen bonding and high degrees of crosslinking give rise to many salient features observed in epoxy-amine thermosets, including corrosion resistance, electrical resistance, and high tensile, compressive, and flexural strength. However, despite these strengths, their reprocessibility and recyclability remain challenges, potentially addressable via design of epoxy-amine building blocks comprising dynamic covalent bonds. This work focuses on design and synthesis of covalent adaptable epoxy-amine networks based on dynamic transesterification exchange. We report the scalable synthesis of ester-bridged epoxide monomer via acid-catalyzed Fischer esterification followed by epoxidation with epichlorohydrin. Epoxy-amine networks were then synthesized by reacting ester-bridged bisepoxide precursors with series of commercially available diamines. Thermal cure of epoxy-amines provided thermosets capable of undergoing stress relaxation and reprocessing, with the efficacy of transesterification dictated by the identity and loading levels of Lewis acid and a Lewis base as external exchange co-catalyst. Thermogravimetric analysis and differential scanning calorimetry were used to establish the curing profile of the material. Dynamic mechanical analysis was performed to determine the stress relaxation behavior, thermo-mechanical properties and reprocessibility of the materials.
Copyright
Pritha Bhunia, 2025
Recommended Citation
Bhunia, Pritha, "Investigation of Dynamic Transesterification in Epoxy-Amine Vitrimers" (2025). Dissertations. 2409.
https://aquila.usm.edu/dissertations/2409
Included in
Organic Chemistry Commons, Polymer and Organic Materials Commons, Polymer Chemistry Commons