The SPI mark of the PLA material

The society of plastics industry (SPI) stipulates that the digital identification code of polylactic acid material is "7". In Belgium, recycling polylactic acid has been used as a pilot country. The recycling of polylactic acid is different from that of other polymers. Waste polylactic acid plastics will be collected in special containers and degraded into small molecular monomers by pyrolysis, hydrolysis and other methods, and then the monomer lactic acid will be synthesized into polylactic acid raw materials with certain properties by the manufacturer, which will be used again in the market.