Pla (polylactic acid) is a new type of bio-based and renewable biodegradable material, which is made of starch from renewable plant resources such as corn, cassava, etc. . The production process of polylactic acid is pollution-free, and the product can be biodegradable and recycled in nature, so it is an ideal green polymer material. Polylactic acid has good heat stability, processing temperature from 170 °C to 230 °C, and good solvent resistance. The products made from polylactic acid can not only be biodegradable, but also have good Biocompatibility, Gloss, transparency, handle and heat resistance, also has a certain resistance to bacteria, flame retardant and UV resistance, so it is very widely used, can be used for fruit, vegetables, eggs, cooked and baked food, hard packaging, can also be used for sandwiches, biscuits and flowers and other goods packaging.