Autooxidation is the process by which organic materials degrade in the presence of air, light and heat. Its autocatalytic nature is thought to arise from the fact that the radical species formed upon cleavage of covalent bonds are not only capable of further damaging and “unzipping” the polymer via various transfer and elimination reactions, but they are also capable of undergoing intermolecular transfer reactions. These latter reactions are crucially important as they transfer the radical centre to other polymer chains so that one initial bond cleavage reaction (which is a high energy process) damages not just one initial polymer, but many 100s or 1000s of them. However, recently we have discovered these crucial transfer reactions should not actually happen for most types of polymer and are most likely occurring as a result of defect structures in the polymer backbone. We’ve also shown that these defect structures can play a key role in initiating oxidative bond cleavage. We are now using these findings to develop more inherently stable polymers.
Selected recent publications:
- Lee R. & Coote M.L. (2013) New insights into 1,2,4-trioxolane stability and the crucial role of ozone in promoting polymer degradation Phys. Chem. Chem. Phys., 15, pp. 16428-16431.
- Gryn’ova, G., Ingold, K. U., & Coote, M.L., (2012) New Insights into the Mechanism of Amine / Nitroxide Cycling During the Oxidative Degradation of Organic Materials, J. Am. Chem. Soc., 134, pp. 12979−12988.
- Gryn’ova, G., Hodgson, J.L., & Coote, M.L. (2011) Revising the Mechanism of Polymer Autooxidation Org. Biol. Chem., 9, pp. 480–490