Synthesis of Stable Organic Radical Homo- and Co-Polymers and Their Applications in Solid-State Devices
Abstract
This thesis outlines the synthesis and characterization of a stable organic radical homopolymer incorporating nitronyl nitroxide radicals, as well as the synthesis and characterization of random and block co-polymers incorporating nitronyl nitroxide and 6-oxoverdazyl radicals.
The nitronyl nitroxide homopolymer was synthesized using ring-opening metathesis polymerization (ROMP), yielding polymers with controlled molecular weights and narrow molecular weight distributions. Studies of polymer growth as a function of time and monomer:catalyst ratio revealed the ROMP to be well-behaved. Spectroscopic analysis of the polymer showed that the radicals possessed high radical content, indicating that they are tolerated by ROMP. Conductivity studies of thin-films made of the nitronyl nitroxide polymer were performed, exhibiting memory effects.
The nitronyl nitroxide and 6-oxoverdazyl random and block co-polymers were also synthesized using ROMP. It was found that the order of polymerization was key towards generating the block co-polymers. The co-polymers were fully characterized using spectroscopic, thermal, and electrochemical methods. Both radicals were incorporated into the co-polymers, and it was found that there was slightly more nitronyl nitroxide incorporation into the polymers than expected, which was attributed to its faster reaction rate.
Overall, this work examines the implementation of stable radicals into polymers, while also probing their behaviour as the functional component of solid-state electronics.