Aqueous Metallosupramolecular Micelles with Spherical or Cylindrical Morphology

Supramolecular AB diblock copolymers have been prepared by the sequential self-assembly of terpyridine end-functionalized polymer blocks using Ru(III)/Ru(II) chemistry. Since this synthetic strategy has been used to attach hydrophobic polystyrene, PS, or poly(ferrocenylsilane), PFS, to a hydrophilic poly(ethylene oxide) block, amphiphilic metallo-supramolecular diblock copolymers have been obtained. These compounds form micelles in water, that were characterized by a combination of dynamic and static light scattering, transmission electron and atomic force microscopies. These techniques revealed the formation of spherical micelles for the PS-based systems while rod-like micelles are observed for the PFS-containing copolymer. This difference is attributed to the propensity of PFS to crystallize in the micellar core.