On the stability of initiators for surface-initiated controlled radical polymerization

The covalent attachment of polymers has emerged as a powerful strategy for the preparation of multi-functional surfaces. Patterned, surface-grafted polymer brushes provide spatial control over a variety of physical properties and allow for fabrication of ‘intelligent’ substrates which selectively adapt to their environment. However, the route towards such patterned polymer brush surfaces often remains challenging, creating a demand for more efficient and less complicated fabrication strategies. Here, we describe recent advances in our group in reduction photolithography to produce topographically and chemically pattern polymer brushes by using light-mediated controlled radical polymerization. We highlight recent work on expanding our technique towards photoinduced electron/energy transfer (PET) reversible addition–fragmentation chain transfer (RAFT) polymerization. We present findings regarding the long-term stability of the surface-grafted initiating sites and discuss reproducibility of SI-PET-RAFT and other polymerization techniques.