With the continuous development of the social economy and the continuous growth of the global population, the earth’s resources have been severely exploited, and environmental and energy problems such as global warming and the depletion of oil resources have become more and more severe. Among them, polymer compounds synthesized from petroleum and other resources are used in The pollution to the environment in the process of production, consumption, and abandonment has become increasingly prominent, and people have realized the importance of protecting the environment. Therefore, in recent years, non-petroleum-based degradable materials have attracted more and more attention. Among the many biodegradable materials, polylactic acid, as a new type of environmentally friendly polymer material, has gradually attracted people's attention.
Polylactic acid (PLA), also known as polylactide, is a polyester polymerized with lactic acid as a raw material. Polylactic acid has excellent biodegradability, compatibility and absorption. Polylactic acid is a non-toxic, non-irritating synthetic polymer material. Its raw material is lactic acid, which is mainly derived from the fermentation of starch (such as corn and rice). It can also be obtained from cellulose, kitchen garbage or fish waste. PLA has a wide range of raw materials, and products made from it can be directly composted or incinerated after use, and ultimately can completely reduce CO2 and H2O, meeting the requirements of sustainable development. The good transparency and certain toughness, biocompatibility and heat resistance of PLA are the main reasons why it is widely used. In addition, PLA has thermoplastic properties and can be used in many fields. Products prepared with it, such as packaging materials, fibers, etc., are mainly used for disposable products such as disposable tableware and packaging materials, automobile doors, floor mats and car seats, etc. Clothing, electrical appliances and medical and health fields. Compared with traditional petrochemical products, the energy consumption in the production process of polylactic acid is only 20%-50% of that of petrochemical products, and the carbon dioxide produced is only 50% of that of petrochemical products. Therefore, the development of polylactic acid degradable materials is very necessary to alleviate global environmental and energy problems.
【characteristic】
1. Biodegradability
Compared with traditional plastics, polylactic acid can be degraded into CO2 and H2O by microorganisms and light. Its degradation products are non-toxic and harmless, and will not pollute the environment. The monomer for the production of polylactic acid is lactic acid, and lactic acid can be produced by fermentation of crops or agricultural by-products such as wheat, rice and sugar beet. Therefore, the raw materials for the production of polylactic acid are renewable. As an emerging biodegradable material, polylactic acid has a wide range of applications.
2. Biocompatibility and absorbability
Polylactic acid can be hydrolyzed by acid or enzyme to produce lactic acid in the human body. As a metabolite of cells, lactic acid can be further metabolized by enzymes in the body to produce CO2 and H2O. Therefore, polylactic acid is non-toxic and harmless to the human body, and has good biocompatibility and bioabsorbability. Polylactic acid has passed the certification of the US Food and Drug Administration and can be used as a biological material implanted in the human body.
3. Physical processability
As a thermoplastic polymer material, polylactic acid has good plasticity and physical processing properties, high melting point and crystallinity, good elasticity and flexibility, and excellent thermoformability. Polylactic acid materials, like polypropylene (PP), polystyrene (PS), and polyphenylene ether resin (PPO), can be extruded, stretched, and injection blow molded, and other high-molecular materials can be processed.
PLA straw
The PLA degradable straw is made of a new type of bio-based and renewable biodegradable material. This material is called PLA, also known as polylactic acid. It is made of starch raw materials proposed by renewable plant resources (such as corn, cassava, etc.) and is degradable. The ordinary plastic straws are not degradable.
PLA polylactic acid straws use starch as the main raw material. Since starch is a biodegradable natural polymer, it can be decomposed into water and carbon dioxide in 45 days under composting conditions after being discarded. It does not pollute the environment; while ordinary plastic straws are discarded after use. It will not automatically degrade and will pollute the environment to a certain extent.
The appearance and performance of PLA degradable straws are close to traditional straws made of polypropylene. The product has good gloss and transparency, and has the advantages of safety, hygiene, environmental protection, and biodegradability. The shelf life can be up to 12 months.
The raw material of the pla straw is natural raw materials such as corn or starch.
The PLA degradable straw is made of a new type of bio-based and renewable biodegradable material. This material is called PLA, also known as polylactic acid.
Because corn and starch are a kind of biodegradable natural polymer, they are decomposed into glucose under the action of microorganisms, and then decomposed into water and carbon dioxide. After using the pla straw, it can be buried in the soil or under other composting conditions for 45 days to be decomposed into water and carbon dioxide.
The carbon dioxide produced directly enters the soil organic matter or is absorbed by plants, and will not be discharged into the air, and will not cause the greenhouse effect. It effectively avoids the white pollution problem caused by plastic products, and truly originates from nature and belongs to nature.