Briefly introduce the four major categories of biodegradable materials

At present, it is mainly divided into four categories: polylactic acid (PLA), polylactic acid ester (Phat), and polylactic acid ester (PBAT).

Polylactic acid: It is one of the most common biodegradable plastics made primarily from lactic acid. The production process of polylactic acid is pollution-free and the product is biodegradable. Waste polylactic acid at 55 ℃ can be decomposed into carbon dioxide and water through the action of composting or oxygen enrichment and microorganisms, achieving natural material circulation without affecting the environment. At present, the ring opening polymerization technology of lactide is mainly used for the production of polylactic acid. Firstly, lactic acid dehydrates to produce oligomers, then decomposes polymers to produce acrylic acid, and then undergoes ring opening polymerization to produce polylactic acid. Polylactic acid also has reliable biocompatibility, biodegradability, good mechanical properties, easy processing, and is widely used in the fields of packaging, textiles, agricultural plastic films, and biomedical polymers. The disadvantage of PLA is that the degradation conditions are relatively harsh. However, due to the relatively low cost of polylactic acid in biodegradable plastics, its consumption ranks among the top.

PBS: Made by shrinking succinic acid and 11.4-butanediol. PBS is easily converted into carbon dioxide and water by various microorganisms or enzymes in nature, and has strong biocompatibility, biological absorption, and heat resistance. PBS can be used in packaging film, tableware, foam packaging materials, daily bottles, medicine bottles, agricultural film, pesticide fertilizer slow release materials and other fields. Due to the limited availability of succinic acid raw materials in China, the production of PBS derivatives PBAT and PBSA meets the requirements. Its performance and performance. PBS is basically similar, but its processing performance is not as good as PBS.

PBAT: It is a thermoplastic biodegradable plastic. Fatty acids and butanediol are usually produced through petrochemicals or biological fermentation. It has strong ductility and tensile strength, as well as good heat resistance and impact resistance. PBAT has good film-forming properties and convenient film blowing, and is widely used in the fields of disposable packaging films and agricultural films. PBAT has excellent biodegradability and is one of the most active degradation materials in the research and market application of degradable plastics.

PHA: PHA biodegradable plastics include categories such as polyhydroxyalkanoates (PHA) and poly-3-hydroxybutyrate (PHB). PHA has a very unique degradation method. PHA can completely degrade β - hydroxybutyric acid, carbon dioxide, and water in vivo after use. Thermoplasticity and thermoplasticity are poor, but the temperature during thermoplastic processing is unstable. Can be used for disposable goods, medical equipment surgical gowns, packaging bags, composting bags, medical sutures, repair equipment, gauze, straightening needles, anti mucous membranes, and stents.