Biodegradable plastics are mainly used in packaging, fiber, agriculture, injection molding and other fields. Among them, the packaging industry is the most widely used, and the injection molding application market is the main driving force for the growth of biodegradable plastics. At present, Europe and the United States is the main market for biodegradable plastics.
Biodegradable plastic refers to microorganisms that exist in nature, such as under conditions such as soil and/or sand, and/or under specific conditions such as composting conditions or under anaerobic digestion conditions or in aqueous culture fluids. Bacteria, mold and algae cause degradation and eventually completely degrade into carbon dioxide (CO2) or/and methane (CH4), water (H2O) and mineralized inorganic salts of the elements contained therein, as well as new biomass plastics.
Polylactic acid (PLA) is a new type of biodegradable material made from starch raw materials proposed by renewable plant resources such as corn. It has good biodegradability, can be completely degraded by microorganisms in nature after use, and finally produces carbon dioxide and water, which does not pollute the environment. This is very beneficial to the environment and is recognized as an environmentally friendly material. It is understood that the amount of PLA accounts for 45.1% of biodegradable plastics, which is the well-deserved main force!
The degradation of polylactic acid is divided into two stages: 1) first, hydrolysis to a lactic acid monomer; 2) lactic acid monomer is degraded into carbon dioxide and water by the action of microorganisms. Food cups made of polylactic acid can be completely degraded in just 60 days, truly achieving both ecological and economic effects.
At present, PLA is mainly used for food packaging such as biodegradable packaging bag and 3D printing that everyone is most concerned about.
In addition to PLA, what are biodegradable plastics?
1. Poly 3-hydroxyalkanoate (PHA)PHA is a different structure of aliphatic copolyester synthesized by microorganisms fermented by various carbon sources. The most common of these are poly-3-hydroxybutyrate (PHB), polyhydroxyvalerate (PHV) and a copolymer of PHB and PHV (PHBV). The main purposes are: disposable tableware, non-woven fabrics, packaging materials, agricultural film, toys, coatings, glue, fiber and other degradable products.
2. Polyε-caprolactone (PCL)
Poly-ε-caprolactone (PCL) is a low-melting polymer obtained by ring-opening polymerization of ε-caprolactone, which has a melting point of only 62 °C. The degradability study of PCL has been started since 1976, and in the anaerobic and aerobic environment, PCL can be completely decomposed by microorganisms. Compared with PLA, PCL has better hydrophobicity, but the degradation rate is slower; at the same time, its synthesis process is simple and the cost is low. PCL has excellent processing properties and can be made into films and other products by ordinary plastic processing equipment.
Biodegradable Drawstring Bag
PBS with aliphatic succinic acid and butanediol as the main raw materials can meet the demand through petrochemical products, and can also be produced through bio-fermentation through natural renewable crop products such as starch, cellulose and glucose. Green circulation production from nature and return to nature. Moreover, raw materials produced by the bio-fermentation process can significantly reduce the cost of raw materials, thereby further reducing the cost of PBS.
Polybutylene succinate (PBS) is extremely versatile and can be used in packaging, for example, biodegradable vegetables bag, tableware, cosmetic bottles and pharmaceutical bottles, disposable medical supplies, agricultural films, pesticides and fertilizers, and biomedical polymers.
4. Polyvinyl alcohol (PVA)Water-soluble PVA film is a new type of plastic product that has emerged internationally. It utilizes the film-forming properties of PVA, water and biological degradation characteristics, and can be completely degraded into CO2 and H2O. It is a veritable green high-tech environmental protection packaging material.