Abstract

This lecture builds upon the catalysis described in the first lecture and describes a recently discovered catalysis which allows a single catalyst to switch between different catalytic cycles by control of the chain end-group chemistry. In 2014, the Williams research team discovered a new type of switchable polymerization catalysis , whereby a single catalyst selectively enchain monomer mixtures to produce block sequence selective polymers.[5] This lecture will set out the pathway from this discovery and outline the evidence supporting switchable catalytic process, including kinetic studies, and the underpinning mechanistic hypothesis.[6] It will also demonstrate the process is generalizable to a range of new and known catalysts and monomers.[7] It focuses on the controlled and selective formation of multi-block polymers comprising ester, ether and carbonate linkages. It also identifies early-stage research towards applications for such polymers as thermoplastic elastomers, rigid plastics and medical materials⁸