Polylactic acid (PLA) is a new type of bio-based and renewable biodegradable material, made from starch raw materials proposed by renewable plant resources (such as corn, cassava, etc.). The production process is non-polluting and has good biodegradability. After use, it can be completely degraded by microorganisms in nature under specific conditions,and eventually generate carbon dioxide and water, which does not pollute the environment.This is very beneficial to environmental protection and is a recognized environmentally friendly material.