Ring-opening polymerization of ε-caprolactone using novel dendritic aluminum alkoxide initiators

Abstract

We have prepared two novel dendritic aluminum alkoxide initiators for ring-opening polymerization. An aluminum trialkoxide dendrimer was prepared from triethylaluminum and dendritic alcohol, and an aluminum dendrimer embedded by bidentate ligation of the dendritic α-glycol was prepared from diethylaluminum ethoxide and a novel dithiothreitol-derived dendritic ligand. These aluminum dendrimers were each applied as an initiator for ring-opening polymerization of ε-caprolactone, and each one showed high reactivity. Furthermore, when the dithiothreitol-derived dendrimer was used as the initiator, the higher the generation from which the dendrimer was derived, the narrower the polydispersity (Mw/Mn) of poly(ε-caprolactone) was. This relationship between the generation of the dendritic initiator and polydispersity is one of the positive dendritic effects.