Reusable polymer brush-based photocatalysts for PET-RAFT polymerization

This contribution discusses the control over polymerizations using a heterogeneous photocatalyst based on fluorescein polymer brushes tethered to micron-scale glass supports (FPB@SiO₂). FPB@SiO₂-catalyzed photoinduced electron/energy transfer-reversible addition-fragmentation chain transfer (PET-RAFT) polymerization is shown to provide high conversions, controlled molecular weights and narrow molecular weight distributions for a variety of monomers. Moreover, the beads can catalyze PET-RAFT on gram scales, in the presence of oxygen, while allowing full catalyst recovery through simple filtration. Finally, their high shelf-life allows for multiple polymerizations and user-friendly access to precision macromolecules under mild reaction conditions even after prolonged (months) storage time.