Developing Functional Polymeric Materials Using Dynamic Chemistry

The growing demands for multifunctional materials in biomedical, electronic, and artificial skin applications have acerated the development in polymer chemistry. This thesis focuses on the design, synthesis, and application of smart polymeric materials across three integrated research areas: dynamic covalent chemistry, polymer and hydrogel composites, and additive manufacturing. Central to this work is the development and application of dynamic aminal bonds as reversible covalent linkages capable of imparting self-healing, stimuli-responsive, and adaptive functionalities to polymer networks. Chapter 1 reviews the mentioned key areas in details and emphasises the development of modern advanced polymer design, synthesis, characterization, manufacturing and remaining challenges. Chapter 2 systematically investigates dynamic aminal covalent chemistry through the functionalization of linear polyethyleneimine with various functional aldehydes, establishing tuneable and reversible polyaminal systems under mild, catalyst-free conditions. In addition, the dynamic aminal exchange behaviour was studied. Chapter 3 introduces the development of a multifunctional polymer composite by the incorporation of carbon nanotubes, featuring dynamic hydrogen bonds and pi-pi interactions, achieving high mechanical stiffness, electrical conductivity, and self-healing ability. Building upon this, Chapter 4 presents the synthesis of a 3D printing-compatible hydrogel composite, integrating dynamic aminal crosslinking and stabilized multiwalled carbon nanotubes (MWCNTs) to offer controlled swelling, mechanical robustness, and frequency-responsive conductivity. These innovations exhibited synergistic molecular design, nanofiller incorporation, and precision manufacturing converge to overcome conventional performance limitations. Lastly, Chapter 5 summarizes my work during candidature and lists suggestions for future research.