Biodegradable plastics are mainly used in the high-end market, such as medical products, drug delivery materials, and materials for 3D printing. Biodegradable plastics such as PLA, PCL and PHAs have good biocompatibility and can be synthesized by molecular design to achieve adjustable performance, thus they have potential in the high-end market.
1、Polylactic acid (PLA)
PLA is a polymer obtained by polymerizing lactic acid as the main raw material, which is a kind of bio-based biodegradable plastic that has been commercialized.
The main raw material, lactic acid, is made from corn starch, and can also be made from beets or grains through fermentation to reduce the cost, the production of PLA is abundant and renewable raw materials, production of pollution-free, the product can be biodegradable.
PLA has good bio-solubility, bio-absorbability and solvent resistance, and can be processed in various ways, such as blown film and extrusion molding.
PLA also has good flame retardancy, antibacterial properties, and in the degradable thermoplastic polymers, PLA has the best thermal resistance, so no special equipment and operation process, the application of conventional processing can be melt spinning.
2、Polycaprolactone (PCL)
Polycaprolactone is an aliphatic straight-chain polyester, different from PLA, it is a commercialized bio-based degradable plastic with very soft texture, large ductility, and excellent biocompatibility, memory, biodegradability, widely used in various fields, especially in the medical field.
Polycaprolactone is soft, easy to process, and has excellent performance. It is commonly used as tissue engineering scaffold material in the medical field, and can be absorbed and excreted by the human body.
3、PHAs
PHAs are biodegradable plastics produced by bacterial fermentation, and can be used as an intramolecular carbon source and energy reserve, and become granules gathered in the cytoplasm.
The fermentation products are mainly carbohydrates such as glucose. Different fermentation conditions can produce different types of PHAs.
Due to their expensive price and good biocompatibility, PHAs are more often used in the medical field.
For example, medical sutures, prosthetic devices, repair patches, bandages, cardiovascular patches, guided tissue repair, articular cartilage repair scaffolds, nerve conduits, tendon repair devices, artificial esophagus and wound dressings, etc.
In conclusion, the market demand for biodegradable plastics will grow rapidly in the coming years, and the total global demand for biodegradable plastics is expected to reach about 3.22 million tons by 2020, with an average annual demand growth rate of over 16%.
Since biodegradable plastics are increasingly used in medical, production and manufacturing industries, the development of biodegradable and environment-friendly plastics industry is the best way to effectively solve the problem of "white pollution", avoid the hazards of plastics and the risk of cancer, and protect the environment.