Degradable plastic refers to a kind of plastic whose products can meet the requirements of use and whose performance remains unchanged during the storage period but can be degraded into environmentally sound substances under natural environmental conditions after use.
1) Upstream: The raw material is mainly crushed corn and other shell crops, and then starch is extracted from it, and then the starch is made into unrefined glucose.
2) The production includes three steps of "fermentation-prepolymerization-polymerization". The first step is to ferment glucose in a manner similar to the production of beer or alcohol to obtain lactic acid with high optical purity. In the second step, the lactic acid monomer is transformed into an intermediate product-water-reduced lactic acid, or lactide, through a special concentration process. In the third step, the lactide monomer is vacuum-purified, and then a solvent-free dissolution process is used to complete the ring-opening action to polymerize the monomer.
Bio-based degradable plastics represented by PLA are mainly derived from food and microorganisms, with renewable sources, no pollution to the environment after use, and conform to the national sustainable development strategy, although the current raw material costs, technology, and equipment costs are relatively high. But with the further development of the technological level and pla extruder machine scale, the cost has decreased correspondingly, and the development prospects are bright.