Surface Nanostructures Fabricated by Polymerization-Induced Surface Self-Assembly

Surface properties of materials are strongly dependent on surface chemistry and surface structures. The fabrication of hierarchical surface nanostructures will endow solid surfaces with new functionalities and properties. In this research, we propose the polymerization-induced surface self-assembly (PISSA) approach for surface reconstruction. In this approach, two macro-CTAs, one grafted on silica particles and the other molecularly dissolved in solution, were used in reversible addition-fragmentation chain transfer (RAFT) dispersion polymerization, and surface micelles (s-micelles) with different morphologies and sizes on silica particles were fabricated. Kinetics studies demonstrate that there are two critical points on a plot of in ([M](0)/[M](t)) vs polymerization time, corresponding to the onsets of surface assembly and the self-assembly of block copolymers. The morphology of s-micelles is dependent on the monomer conversion and the length of macro-CTA. For macro-CTA with short chain length, with an increase in monomer conversion the s-micelles experience a morphology change from spherical s-micelles to layered structures. For macro-CTA with long chain length, the average size of s-micelles increases with monomer conversion. In this research, we demonstrate PISSA can be used as a versatile method for surface modification.