Abstract

This article focuses on the controlled synthesis and properties of polylactide (PLA) in regard to its microstructure and the design of new related materials, with particular attention on nanocomposites built up from PLA and organoclays, ie, organo-modified layered silicates (OMLS). As far as the ring-opening polymerization of lactide is concerned, the selectivity and stereoelectivity of novel (catalytic) initiating systems are discussed using different combinations of lactide isomers, catalysts–initiators, and ligands. A series of biodegradable PLA/OMLS nanocomposites prepared by either solution mixing, melt intercalation, or in situ intercalative polymerization is described. All these nanocomposites exhibit dramatic improvements in mechanical and many other materials key-properties as compared with those of unfilled pristine PLA. These improvements include flexural and thermal properties, heat distortion temperature, oxygen permeability barrier, and rate of crystallization. The future of PLA-based materials is also discussed with special attention to the environmental impact.