Abstract
In the field of supramolecular and polymer chemistry, there is a focus on the structural design of oligomers and polymers at the molecular level. Factors such as intramolecular and intermolecular interactions, stereochemistry, crosslinking, entanglement, chemical bonding, chain length, and side-chain functionality can dictate the properties of resulting macromolecules and polymers. The connection between polymer structures and their properties is often intricate and non-linear, making it difficult to accurately predict. Thus, it becomes necessary to study polymer structures and their resultant properties through traditional models or experiments. In the field of mechanically interlocked molecules, the potential properties of catenane and poly[n]catenane mechanical bonding and topologies have garnered wide interest due to the potential of their toughness and flexibility in materials. These properties make these [n]catenanes and poly[n]catenanes promising candidates for making complex molecular machines, or smart soft materials, respectively. While many variations of [n]catenane complexes have been explored, the straightforward preparation of higher molecular weight linear [n]catenanes has only relatively recently been attempted. In many cases, the synthesis of any catenane is difficult, low-yielding, and usually a slow process. The development of more efficient synthetic protocols for functional catenanes presents a continual, desirable challenge to supramolecular chemists. In the field of traditional polymer chemistry, the synthesis of carbon fiber and the development and enhancement of their structural properties and applications has been widely studied and is of high interest in the community due to the large range of carbon fiber applications in industry and society and its versatile, high-yield macroscopic properties. However, carbon fiber exploration and novel advances have predominantly been concentrated in its post-synthesis, bulk material engineering. To date, development into the synthesis and transformation of polyacrylonitrile (PAN), the polymer precursor to carbon fiber, has been limited to mainly 70,000 – 200,000 g/mol molecular weight polymers due to the limitations of control of the free-radical polymerization of acrylonitrile monomer. While this can still result in intermediate modulus carbon fiber, there is a large potential property enhancement that is left unstudied for PAN, and ultimately carbon fiber. Molecular-level advancement of PAN and carbon fiber synthesis leaves much room for improvement. Overall, the synthetic gap between the synthesis and development of the material properties of catenanes and PAN-based precursor polymers towards carbon fiber need to be bridged.
Committee Chair
Jonathan Barnes
Committee Members
John-Stephen Taylor; Kevin Moeller; Marcus Foston; Vladimir Birman
Degree
Doctor of Philosophy (PhD)
Author's Department
Chemistry
Document Type
Dissertation
Date of Award
7-15-2025
Language
English (en)
DOI
https://doi.org/10.7936/jxww-wj29
Recommended Citation
Tran, Sheila, "Using “Click” Chemistry and Post-Polymerization Modification to Synthesize Well-Defined Linear Oligocatenanes and Polyacrylonitrile" (2025). Arts & Sciences Theses and Dissertations. 3620.
The definitive version is available at https://doi.org/10.7936/jxww-wj29