Tuning the morphologies of amphiphilic metallo-supramolecular triblock terpolymers: from spherical micelles to switchable vesicles

A well-defined poly(styrene)-block-poly(para-trifluoromethylstyrene)-[Ru]-poly(ethylene glycol) (PS–b–PTFMS–[Ru]–PEG) amphiphilic metallo-supramolecular triblock terpolymer containing a bis(2,2′:6′,2-terpyridine)ruthenium(II) complex (–[Ru]–) as a connection between the PS–b–PTFMS and the PEG block was successfully synthesized using the concepts of controlled radical polymerization and supramolecular chemistry. Spherical micelles, wormlike micelles, vesicles and hollow tubes were all accessed from this copolymer by varying the polarity of the solvent which provokes a change in the solvophilic to solvophilic ratio within the same macromolecule by dissolution or precipitation of the PTFMS-block. The self-assembled structures with both PS and PTFMS as insoluble blocks are presumed to be multicompartmentalized based on the incompatibility of these blocks. Furthermore, the thermoresponsive behavior of PTFMS allows reversible control over the size and morphology of the self-assembled structures.