The application of PLA in the market is mainly concentrated in the three fields of packaging, medical and textile (fiber), of which the application in the packaging industry is particularly prominent.
(1) PLA film
PLA film mainly includes high transparent film, heat shrinkable film, pellet blend blown film bag and PLA-based composite film. PLA film can replace traditional film materials as a new packaging material. For example, Wal-Mart supermarket requires the use of fully degradable PLA film bags to replace traditional non-degradable PE bags. Japanese electronic products have also begun to use PLA nano-composite film packaging.
(2) PLA container
Due to the degradability of PLA, it is used to produce water and juice bottles, but the market is limited. Injection-stretch-blow molding is a typical production method of PLA bottles, which is mostly used in short-term shelf food packaging. The transparency and oxygen barrier of PLA bottles are better than PE bottles. Due to the insufficient creep behavior of PLA and low CO2 barrier properties, the application of PLA bottles is limited to non-carbonated beverages. NatureWorks uses PLA bottles to package organic juice beverages, which can guarantee a shelf life of 60 days. The Danish Faerch Plastics Company uses PLA to package low-temperature pasta, meat, salads and other fresh foods, which can achieve a long shelf life. The European market has launched PLA-made yogurt cups and beverage packaging bottles, which can meet EU standards for food containers. Some companies have already developed high-transparency and heat-resistant PLA water bottles, which can meet the application conditions of both transparency and heat resistance (heat-resistant temperature ≥100°C). In the domestic market, PLA is coated on paper to make coated paper cups, which are used for various waterproof and oil-proof food packaging.
(3) PLA foamed material
PLA foamed material is biodegradable and can be used to produce disposable catering utensils (such as fast food boxes, instant noodle bowls, etc.) and cushioning packaging, without white pollution, especially PLA heat-resistant tableware will become more practical . The "Graft" series of disposable tableware is designed with PLA foam material to have a realistic shape of fruits and vegetables, which is both environmentally friendly and beautiful. It is worth noting that foaming is an effective method for low-cost use of PLA. The melt strength of pure PLA is low, and the melt viscosity is not obvious to shearing. It is not suitable for extrusion coating, foaming and other processing methods.
