Combining Late-Transition Metal Insertion Polymerization With Radical Polymerization

The inherent differences in reactivity between activated and non-activated alkenes has prevented their copolymerization using established polymer synthesis techniques. As such, a major challenge in polymer chemistry has been the development of new techniques which can facilitate the polymerization for both classes of monomer in a controlled manner. This dissertation is the culmination of four projects which all center around metal-organic insertion light initiated radical (MILRad) polymerization, a technique established in our group which bridges the gap between polar vinyl monomers and olefins. The first project covers the inception of this technique and its ability to make polar-polyolefin block copolymers with a single palladium diimine catalyst, a feat demonstrated for the first time. The key to this method was blue light irradiation, which switched the catalyst from insertion polymerization to radical polymerization. The second project details the universality of multiple palladium diimine catalysts to generate radicals when irradiated with blue light, which undergo free radical polymerization of acrylic and (meth)acrylic monomers. A metal-to-ligand charge-transfer was identified for all complexes, which is attributed to their ability to undergo metal-carbon bond homolysis. The third project summarizes the mechanism of MILRad polymerization, furthering the ability to undergo controlled living insertion polymerization and subsequent free radical polymerization to make di- and triblock copolymers. Experiments with radical and spin traps confirmed the nature of the radical generation, while also serving as preliminary results for polyolefin functionalization. A common theme with the initial three projects is the ability to make block copolymers with a single catalyst which links together living insertion and free radical polymerization techniques. The final project serves as a complimentary technique which explores polyolefin functionalization radical coupling to install reactive end-groups with functional radical and spin traps. Following functionalization, controlled radical polymerization was shown for both NMP and ATRP from polyolefins. This MILRad functionalization approach allows for dual living insertion and controlled radical polymerization, expanding the scope of monomer families compatible with the system. Taken together, both approaches set precedent for future polyolefin functionalization methodologies within the broader polymer community, revealing the overlooked compatibility between radical coupling and olefin polymerization catalysts.