Photocontrolled reversible supramolecular assemblies of a diblock azo-copolymer based on beta-cyclodextrin-Azo host-guest inclusion complexation

The double hydrophobic block copolymer, poly[6-(4-(phenyldiazenyl) phenoxy) hexyl acrylate]-b-polystyrene (PAzo-b-PS), was synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization. This hydrophobic block copolymer can self-assemble into spherical micelles through beta-cyclodextrin-azobenzene (beta-CD-Azo) host-guest inclusion. Furthermore, the spherical micelles can be dissociated and reassembled by alternating irradiation of UV/visible light. These supramolecular self-assembly and disassembly procedures were studied by dynamic light scattering (DLS), atomic force microscopy (AFM), transmission electron microscopy (TEM) and UV-Vis spectra.