PLA bioplastic production: From monomer to the polymer

Polylactic acid is usually synthesized by ring-opening polymerization of lactide. And, lactide is prepared from lactic acid through polycondensation and depolymerization. Efficient production of lactic acid and lactide plays a positive role in promoting the rapid development of polylactic acid industry. This work sorts out recent progresses of the production of polylactic acid and its precursors (especially lactide) to clarify current research and discuss its future development direction. [Display omitted] Poly(lactic acid) (PLA) plastics is of great significance to the sustainable development of the world. Today, most PLA is prepared by ring-opening polymerization of lactide (LT) synthesized from lactic acid (LA). The production capacity of high-quality LA is the basis for the production of PLA bioplastics. And, as the key intermediate for PLA synthesis, lactide (LT) also has a profound impact on the whole PLA industrial chain. The production capacity of LT is directly related to the application scale of PLA, and chemical purity and optical purity of LT significantly affect the properties of synthesized PLA. In this work, the research progresses on LA, LT, and PLA in recent years are sorted out to provide a comprehensively and systematic review. Apart from the introduction of the whole process of PLA production, this review highlights some of the latest methods with significant advantages in energy consumption, reaction integration, efficiency and yield in the production process.