1. Introduce

Polylactic acid is produced by fermentation of high-gloss pure lactic acid from starch biomass such as corn or straw cellulose. The lactic acid is prepared into ring dimer lactide, and then the lactide is ring-opened and polymerized to produce poly lactic acid. It is not based on petroleum as raw material, with environmental protection, non-toxic, degradable characteristics, is considered to be the most petroleum as raw material, with environmental protection, non-toxic, degradable characteristics, is considered to be the most promising future of new biological materials to shake the traditional position of petro-based plastics(PE, PP, PVC, ect.) and petro-chemical fiber(PET, PTT, PBT, etc.)

For sustainable development, a significant revolution has been made in the world to replace fossil resources with bio-renewable resources. The replacement of petroleum-based polymer material by bio-based polymer materials is inevitable for the development of the material industry, and the bio-based materials has gradually transform to the use of bio-based materials, and it's expected that by 2035, 80% of the world's petro-based materials will be replaced by bio-based materials.

Global production of plastic and chemical fiber is about 500million tons/year, China's consumption is 160~180 million tons/year (including 11-~130 million tons/year for plastic, 50million tons/year for chemical fiber), according to statistics, only 10% of the plastic are recycled. There are 8 million tons of plastic waste flows into the ocean every year. The plastic waste degradation cycle takes more than 450 years in the marine environment. It is reported that by 2050, the total weight of waste plastics in the ocean will exceed that of the fish.