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Author ORCID Identifier
https://orcid.org/0000-0001-5981-3549
AccessType
Campus-Only Access for One (1) Year
Document Type
dissertation
Degree Name
Doctor of Philosophy (PhD)
Degree Program
Polymer Science and Engineering
Year Degree Awarded
2023
Month Degree Awarded
May
First Advisor
Todd Emrick
Abstract
Polymer zwitterions represent an emerging class of materials with enormous potential to advance technologies closely related to people’s lives, such as biomedical development and electronic applications. This thesis exploited innovative synthetic designs to incorporate useful functionalities into polymer zwitterions, particularly fluorinated and reactive groups, and successfully expanded their properties and applications. The core of this thesis relies on the development of novel fluorinated choline phosphate (FCP) monomers, in which the fluorocarbons are directly embedded into the zwitterionic moieties. These novel FCP monomers, in combination with conventional zwitterionic monomers and fluorinated monomers, allow the construction of a library of fluorinated polymer zwitterions with well-controlled compositions and architectures. The FCP polymers proved advantageous for applications ranging from 19F magnetic resonance imaging to fluid-fluid interface stabilization and antifouling coatings. The unique combination of fluorocarbon and zwitterions inspired further study to gain a deeper understanding of the surface properties of FCP polymers. Zwitterionic, FCP, and fluorinated polymer brushes were grafted from Au substrates using surface-initiated atom transfer radical polymerization, and comprehensive wettability and surface energies study were conducted with these functionalized surfaces, with results demonstrating a distinct responsiveness of FCP polymers to the contacting fluid environment. Remarkably, these dynamic FCP coatings afforded similar or better resistance to protein fouling in comparison to conventional zwitterionic or fluorinated polymer-modified surfaces. Furthermore, the FCP polymers were used in a polymer-based DNA packaging system, which was built on previous work on DNA delivery in the Emrick group. The presence of FCP polymers imparted the DNA packaging system with desirable colloidal stability under biologically relevant conditions, partially screened the cationic charge that might cause cytotoxicity, and enabled the tuning of binding affinity for DNA. This polymeric vector formulation holds great potential to improve the safety and efficacy of gene delivery, which is currently the major challenge of field. In addition to fluorinated polymer zwitterions, novel reactive polymer zwitterions containing 1,2-dithiolanes and alkenes were synthesized and used to prepare hydrogels with strain-stiffening properties that are of interest for tissue engineering. Overall, this thesis successfully prepared an array of functional polymer zwitterions with unique designs that hold promise for imaging, therapeutic delivery, and coating applications. Importantly, the novel monomers and polymers established here inspire opportunities and interests to pursue the development of new materials and advance fundamental understanding of their properties.
DOI
https://doi.org/10.7275/34042311
Recommended Citation
Zhou, Le, "MERGING SYNTHETIC AND NATURAL COMPONENTS INTO FUNCTIONAL POLYMER ZWITTERIONS" (2023). Doctoral Dissertations. 2879.
https://doi.org/10.7275/34042311
https://scholarworks.umass.edu/dissertations_2/2879
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License