Dynamic polymer brushes on the surface of silica particles

Synthesis of cleavable PS brushes on the surface of silica particles was reported in this paper. Atom transfer radical polymerization (ATRP) initiator was anchored onto the surface of silica particles via dynamic imine bond, and PS brushes were prepared by surface ATRP of styrene. PS brushes could be cleaved from the surface of silica particles in the presence of trifluoroacetic acid. Based on the dynamic properties of imine bonds, pyrene-labeled silica particles were prepared through dynamic exchange reaction between PS brushes and 1-pyrenecarboxaldehyde. Moreover, silica particles with PS and fluorescein-labeled poly(methyl methacrylate) mixed polymer brushes were synthesized by dynamic exchange reaction. This research demonstrates that dynamic covalent chemistry provides an efficient method for the preparation of “dynamic” polymer brushes on silica particles.