Living and Stereoselective Polymerization of Rac-Lactide by Bimetallic Aluminum Schiff-Base Complexes

A series of bimetallic aluminum Schiff-base complexes have been prepared and characterized. The complexes used as catalysts were applied in the lactide polymerization to test their activities and stereoselectivities. All polymerizations are living, as evidenced by the narrow polydispersities and the good fit between calculated and found number-average molecular weights of the isolated polymers. Isotactic enriched polylactide was obtained by using these complexes. Kinetic studies indicated that the polymerizations are both first-ordered with respect to lactide monomer and catalyst. (c) 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1344-1352