The plastics industry has developed rapidly with the development of petrochemical industry. It has the advantages of easy material acquisition, low price, convenient and lightweight processing, etc. It is widely used in various fields of society and brings great convenience to people's lives. But at the same time, , Because a large number of waste plastic products are difficult to decompose, it constitutes increasingly serious 'white pollution', which hinders social progress and economic sustainable development. As human beings pay more attention to environmental protection, they deal with the waste of polymer materials. Hot topics have received widespread attention around the world.
Therefore, the preparation of environment-friendly biodegradable plastics to replace traditional plastics, research and development of biodegradable plastics become an effective method of pollution control, and biodegradable plastics have also become a hot research direction at home and abroad.
Currently Degradable plastics mainly include biodegradable plastics, photodegradable plastics, light and biodegradable plastics, and water-degradable plastics. Among them, the most in-depth study of biodegradable plastics, the most widely used.
Biodegradable plastic It is a type of plastic that is degraded by the presence of microorganisms such as bacteria, mold (fungi) and algae in the nature. The ideal biodegradable plastic is an excellent use performance, and can be completely decomposed by microorganisms in the environment after being discarded. It is eventually inorganicized into a polymer material that is part of the carbon cycle in nature.
In addition to being biodegradable, biodegradable plastics also have the advantages of renewable raw materials, strong adaptability to the body, and so on, which can be widely used in fields including environmental protection, food containers and packaging, agriculture and forestry, medicine, textiles, electronics, and automobiles.
▲Biodegradable plastics derived from biomass
As biodegradable plastics are used in high-end markets, they mainly include medical supplies, drug release materials, and materials for 3D printing. Biodegradable plastics such as PLA, PCL, and PHAs have good biocompatibility and can be synthesized. Through the molecular design to achieve the controllability of performance, it has potential for development in the high-end market.
▲Biodegradable 3D Printing Consumables
Polylactic acid (PLA)
Polylactic acid It is a polymer obtained by polymerizing lactic acid as its main raw material. It is a biodegradable plastic that has been commercialized. The main raw material is lactic acid from corn starch Made in China, it can also be used Beets or grains After being fermented to reduce costs, raw materials for production of polylactic acid are abundant and reproducible, producing no pollution, and products can be biodegraded.
Polylactic acid has good bio-solubility, bioabsorbability and good solvent resistance, and can be processed in many ways, such as blown film, extrusion molding, etc.
Polylactic acid is also very flame-retardant, bacteriostatic, and among the degradable thermoplastic polymers, PLA has the best heat resistance, so no special equipment and operating procedures are required, and conventional processing techniques can be applied. Melt spinning.
PHAs
PHAs Biodegradable Plastics It is produced by bacterial fermentation and can be used as an intramolecular carbon source and energy reserve, and it becomes aggregates of particles in the cytoplasm. Fermentation is mainly carbohydrates such as glucose. Different fermentation conditions can produce different types of PHAs.
Due to the high price of PHAs and good biocompatibility, PHAs are used in more medical fields. Such as medical sutures, prosthetic devices, maintenance patches, bandages, cardiovascular patches, guided tissue repairs, articular cartilage repair scaffolds, nerves Catheters, tendon repair devices, artificial esophagus and wound dressings.
Polycaprolactone (PCL)
Polycaprolactone It is an aliphatic linear polyester. Unlike PLA, it is a commercially available bio-based biodegradable plastic. It has a very soft texture, great ductility, and excellent biocompatibility and memory. Biodegradable, widely used in various fields, especially in the medical area.
Polycaprolactone is soft, easy to process, and has excellent performance. It is commonly used in tissue engineering scaffold materials in the medical field and can be absorbed and excreted by the body.
According to a research report published by the US consulting firm Frost & Sullivan, in the coming years, the market demand for biodegradable plastics will grow rapidly. It is estimated that by 2020, the global demand for biodegradable plastics will reach about 3.22 million tons, and the average annual growth rate will exceed 16%.
With the white pollution problem and the non-renewable energy crisis becoming increasingly serious, the development and use of biodegradable plastics has become one of the effective ways to alleviate this problem.
▲ Global demand for biodegradable plastics market forecast
With the enhancement of people’s environmental protection awareness and the implementation of national sustainable policies, the development and utilization of biodegradable plastics cannot be slowed down. Due to the increasing use of biodegradable plastics, there is a greater use value in medical care, production, and manufacturing industries. development of Degradable, environmentally friendly plastic Industry, is an effective way to effectively solve 'white pollution' to protect the environment.
From 2009 to 2013, the compound annual growth rate of China's biodegradable plastics production capacity exceeded 21%. Under the stimulation of the favorable national policies and expanding application scope, the market of biodegradable plastics continued to strengthen.
▲Production of China Degradable Plastics
In today's increasingly scarce oil resources, how to effectively use existing resources, save limited resources, and develop new and alternative petroleum-based materials is an important issue to ensure the sustainable development of China's economy. It is also the future direction for the development of the plastics industry.
At present, there are many companies that have announced that they are investing in the construction of fully biodegradable plastics, but there are very few companies that can truly supply large quantities of plastics. Major manufacturers have BASF , Has 140,000 tons capacity, applied to membrane products; North America Natureworks , With 140,000 tons of PLA capacity, at the same time, the new 150,000 tons capacity in Thailand is expected to be put into operation in 2015; only BASF is directly competitive with the company's products, but due to monopoly supply in the industry, the global market is in short supply, so there is still no competitive pressure .
Global Major Biodegradable Plastics Manufacturers and Their Applications ▼
As of 2016, The production capacity of biodegradable plastics in China reached 710,000 tons, and the output reached 520,000 tons. At present, China's major biodegradable plastic manufacturing enterprises have Blonde Technology, Gorgeous Environmental Protection, Hisun Pharmaceutical, Rainbow Elaboration, Xinfu Pharmaceutical, Southeast Wait.
From a product structure point of view, in addition to starch plastics, PBS is the largest domestic biodegradable plastic products.