From living to controlled aluminium alkoxide mediated ring-opening polymerization of (di)lactones, a powerful tool for the macromolecular engineering of aliphatic polyesters

The aluminium alkoxide mediated ring-opening polymerization of (di)lactones offers a great versatility to the point where the main situations covered by the definition of living and controlled polymerizations can be illustrated. Furthermore, substitution of a coordination-insertion mechanism for the traditional anionic polymerization of these monomers results in species of lower reactivity and in a kinetic control of the polyaddition reaction. This control, combined with the use of Al alkoxides of different structures and functionalities, has opened the way to the macromolecular design of a family of biocompatible and biodegradable polyesters, e.g., controlled synthesis of telechelic polymers, block and graft copolymers, and polymers of various molecular architectures. These polymers can be used as such, or as building parts of more sophisticated polymeric assemblies.