Polylactic acid is a polymer obtained by polymerizing lactic acid as the main raw material and is a new type of biodegradable material. Polylactic acid, also known as polylactide, belongs to the polyester family.
Polylactic acid (H-[OCHCH3CO]n-OH) has good thermal stability, processing temperature is 170～230℃, has good solvent resistance, and can be processed in various ways, such as extrusion, spinning, biaxial stretching , Injection blow molding. In addition to being biodegradable, products made of polylactic acid have good biocompatibility, gloss, transparency, feel and heat resistance. The polylactic acid (PLA) developed by Guanghua Weiye also has certain antibacterial and flame retardant properties And UV resistance, so it is very versatile, can be used as packaging materials, fibers and nonwovens, etc., mainly used in clothing (underwear, outerwear), industry (building, agriculture, forestry, paper) and medical and health fields.
The advantages of polylactic acid mainly include the following aspects:
(1) Polylactic acid (PLA) is a new type of biodegradable material, made from starch raw materials proposed by renewable plant resources (such as corn). The starch raw material obtains glucose through saccharification, and then fermentes glucose and certain strains to produce high-purity lactic acid, and then synthesizes polylactic acid of a certain molecular weight through a chemical synthesis method. It has good biodegradability, can be completely degraded by microorganisms in nature after use, and eventually generates carbon dioxide and water, which does not pollute the environment. This is very beneficial for protecting the environment and is recognized as an environmentally friendly material. The processing method of ordinary plastics is still incineration and cremation, which causes a large amount of greenhouse gases to be discharged into the air, while polylactic acid plastics are buried in the soil and degraded. The carbon dioxide generated directly enters the soil organic matter or is absorbed by plants, and will not be discharged into the air. Will not cause the greenhouse effect.
⑵Good mechanical and physical properties. Polylactic acid is suitable for various processing methods such as blow molding and thermoplastic. It is easy to process and has a wide range of applications. It can be used to process all kinds of plastic products, packaged food, fast food lunch boxes, non-woven fabrics, industrial and civilian fabrics from industry to civilian use. Further processing into agricultural fabrics, health care fabrics, rags, sanitary products, outdoor UV protection fabrics, tent fabrics, mat surfaces, etc., the market prospects are very promising.
⑶Good compatibility and degradability. Polylactic acid is also widely used in the medical field. For example, it can produce disposable infusion sets, disassembly-free surgical sutures, etc., and low-molecular-weight polylactic acid as a drug sustained-release packaging agent.
⑷In addition to the basic characteristics of biodegradable plastics, PLA also has its own unique characteristics. Traditional biodegradable plastics are inferior to ordinary plastics in strength, transparency and resistance to climate change.
⑸ The basic physical properties of polylactic acid (PLA) and petrochemical synthetic plastics are similar, that is to say, it can be widely used to manufacture various application products. Polylactic acid also has good gloss and transparency, and is comparable to the film made of polystyrene, which is not provided by other biodegradable products.
⑹ Polylactic acid (PLA) has the best tensile strength and elongation. Polylactic acid can also be produced in various common processing methods, such as: melt extrusion molding, injection molding, blown film molding, foam molding and vacuum molding, and The widely used polymer has similar forming conditions, in addition it also has the same printing properties as traditional films. In this way, polylactic acid can be made into various application products according to the needs of different industries.
⑺Polylactic acid (PLA) film has good air permeability, oxygen permeability and dioxodicarbon permeability, it also has the characteristics of odor isolation. Viruses and molds tend to attach to the surface of biodegradable plastics, so there are doubts about safety and hygiene. However, polylactic acid is the only biodegradable plastic with excellent antibacterial and anti-mold properties.
⑻When polylactic acid (PLA) is incinerated, its combustion calorific value is the same as that of incinerated paper, which is half of that of traditional plastics (such as polyethylene). Moreover, incinerated polylactic acid will never release toxic gases such as nitrides and sulfides. The human body also contains lactic acid in the form of monomers, which indicates the safety of this decomposable product.