Transforming Polylactide into Value-Added Materials

The production of chemical building blocks and polymer precursors from biorenewable and sustainable resources is an attractive method to bypass traditional fossil fuel derived materials. Accordingly, we report the organocatalytic recycling of postconsumer polylactide (PLA) into value-added small molecules. This strategy, using the highly active transesterification catalyst triazabicyclodecene, is shown to completely depolymerize PLA in the presence of various alcohols into valuable lactate esters. Using previously used PLA packaging material, the depolymerization is complete in minutes at room temperature and fully retains the stereochemistry of the lactate species. Further, the modularity and utility of this methodology with respect to polyester substrate is detailed by using a variety of functional alcohols to depolymerize both PLA and polyglycolide, with the corresponding ester small-molecules being used to make new polymeric materials. The opportunities to transform waste streams into value-added chemicals and new materials through simple and versatile chemistry hold significant potential to extend the lifecycle of renewable chemical feedstocks. (C) 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 50: 4814-4822, 2012