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As energy prices rise and environmental problems become increasingly prominent, the replacement of traditional petroleum products by biodegradable biomaterials around the world is gradually accelerating. It is expected that the government will also issue corresponding preferential policies and laws and regulations to encourage market application and biodegradation. The prospects for large-scale applications of materials are very optimistic.

Biodegradable materials include polymer materials directly prepared by biotechnology, such as polyhydroxy fatty acid esters (PHA); a class of materials obtained by polymerization of raw materials prepared by biotechnology, such as polylactic acid (PLA), Polybutylene succinate (PBS), polyamino acid, etc.; in addition, starch-based biodegradable plastics, carbon dioxide copolymer aliphatic polycarbonate (APC), etc.

Starch-based biodegradable plastic is a plastic product made by blending starch with other polymers after modification and grafting reaction. It can replace general-purpose plastics in industry and can be used as packaging materials and shockproof materials. Plastic film, food containers, toys, etc.

PLA is a polymer material produced by polymerization of lactic acid as raw material. It has the characteristics of non-toxic, non-irritating, high strength, easy processing and molding, and excellent biocompatibility. The product can be completely degraded after use. Therefore, PLA is one This kind of bio-environmental protection material that can truly achieve the dual effects of ecology and economy is the most active and fastest-growing biodegradable plastic in recent years.

Polybutylene succinate is obtained by polycondensation of succinic acid and butylene glycol, and is currently recognized as a biodegradable plastic with the best comprehensive performance in the world. Because PBS has excellent comprehensive performance, reasonable cost performance, and extremely wide range of uses, it can be used in packaging, tableware, cosmetic bottles and medicine bottles, disposable medical supplies, agricultural films, pesticides and fertilizers slow-release materials, biomedical polymer materials and other fields.

Polyhydroxyalkanoate is a kind of natural polymer polyester, which is an intracellular polyester synthesized by many bacteria under specific conditions. Bacteria of more than 90 genera have been found to synthesize more than 150 different structures of PHA. At present, the commercialized PHA products mainly include polyhydroxybutyric acid (PHB), copolymer of hydroxybutyric acid and hydroxyvaleric acid (PHBV) and copolymer of hydroxybutyric acid and hydroxycaproic acid (PHBHHx).