PLA takes annually renewable resources-corn, cassava and other plants as raw material. After fermentation by microorganisms, lactic acid will be extracted, then PLA will be produced through a process of refining, dehydration polymerization, high temperature pyrolysis and final polymerization. PLA has excellent biodegradable property. After disposal, within one year, it can be degraded into carbon dioxide and water by microorganisms in the soil, and do no harm to our environment. PLA is a kind of aliphatic polyester with basic characteristics of general micro molecule materials. PLA has good mechanical properties, low shrinkage, and is competent to the application of most synthetic plastics, also it's widely used in the production ot package materials, disposable tableware, household electrical appliance shelf, fiber, 3D supplies etc. Because PLA derives from renewable plant resources but not the petroleum-based traditional plastics, so it can be truely realize energy-saving and environmental protection, and PLA is considered to be the most promising new "ecological materiar"