Polymer brush growth by oxygen-initiated RAFT polymerization on various substrates

Abstract

Surface-initiated reversible addition–fragmentation chain transfer polymerization using oxygen (O₂-SI-RAFT) was carried out on various substrates in the presence of air. Using mussel-inspired surface chemistry, material-independent surface coating was possible simply by one-pot modification on silicon, titanium, glass, stainless steel, and nylon substrates. O₂-SI-RAFT polymerization was possible with many different monomers, including methacrylate, methacrylamide, and methacrylic acid. We characterized the excellent growth of polymer brushes on Ti/TiO₂ substrates. In addition, it was possible to polymerize block copolymer brushes by chain extension with a living end group functionality and to form polymer brushes by O₂-SI-RAFT on large surfaces in the presence of air. Field emission scanning electron microscopy (FE-SEM) confirmed that poly(2-hydroxyethyl methacrylate) (PHEMA) brushes grew to 856 nm on the Ti/TiO₂ substrate, representing the highest growth by SI-RAFT polymerization reported to date.