The stereochemistry of a molecule relates to the relative spatial arrangement of its atoms. Controlling the stereochemistry of a polymer is highly desirable as this can affect its physical properties, such as its crystallinity, melting point, solubility and mechanical strength, as well as its ability to self assemble chiral molecules. Stereoregular polymers are normally prepared using expensive transition metal catalysts, which typically require demanding reaction conditions (such as high purity, low temperatures and/or high pressures). Extending stereocontrol to free radical polymerisation has been a long sought goal, as free-radical processes tend to require less expensive reagents, less demanding reaction conditions, are applicable to a wider range of monomers, and are therefore usually preferred industrially. We are using a combination of theory and experiment to better understand why current control strategies are failing, and to thereby develop effective stereocontrol agents. In the course of this work, we have recently discovered that Lewis acids, whilst typically poor control agents, are effective propagation catalysts for radical polymerization, and may thus be used to improve other aspects of microstructural control.
- Smith, L.M., & Coote, M.L., (2013) Effect of temperature and solvent on polymer tacticity in the free-radical polymerization of styrene and methyl methacrylate, J. Polym. Sci. Part A: Polym. Chem., 51, pp. 3351–3358
- Noble B. B., Smith L. M., & Coote M.L., (2014) The Effect of LiNTf2 on the Propagation Rate Coefficient of Methyl Methacrylate Polym. Chem., 5, pp. 4974-4983.