Polylactic acid or polyactide (PLA) is a biodegradable and bioactive polyester made up of lactic acid building blocks. It was first discovered in 1932 by Wallace Carothers by heating lactic acid under vacuum while removing condensed water. During the early times, only low-density PLA was produced. By using lactide as a raw material and through the process of ring-opening polymerization, a high-density version of PLA was finally developed.
Early applications of high-density PLA were mostly limited to biomedical areas due to its ability to be safely absorbed biologically. Over the past decades, the development of economical production methods and a rising environmental consciousness in consumers lead to the widespread use of PLA as packaging material for consumer goods. PLA is manufactured from renewable sources and is compostable, addressing problems in solid waste disposal and lessening our dependence on petroleum-based raw materials. It is currently the second most produced and consumed bioplastic in the world in terms of volume.