Scalable depolymerizing transesterification and amidation of (poly)lactic acid (PLA) enabled by resonant acoustic mixing (RAM)

Abstract

This study presents a scalable mechanochemical method for the upcycling of (poly)lactic acid (PLA) into industrially valuable alkyl lactate esters via organocatalytic depolymerizing transesterification enabled by resonant acoustic mixing (RAM). The process is characterized by its simplicity, requiring neither grinding media nor a co-solvent and utilizing nearly stoichiometric amounts of an alcohol reaction partner in the presence of an inexpensive, easily accessible catalyst. Additionally, mechanochemistry is successfully extended to the upcycling of post-consumer PLA for the synthesis of various substituted esters and lactamides.