With the update of packaging, we have been looking for better materials that can have good practicality, even higher than the practicality of current materials, meanwhile can also protect the environment. At present, with the replacement of packaging materials, biodegradable materials have come into being. So what are biodegradable materials?
"Biodegradable materials" refer to materials that can be decomposed into low molecular weight compounds by microorganisms (such as bacteria, fungi, algae, etc.) or their secreted enzymes under certain conditions, and finally converted into harmless substances such as water, carbon dioxide and biomass.
These materials usually have specific chemical structures and physical properties that enable them to degrade under biological action in the natural environment. The degradation process of biodegradable materials may be affected by many factors, including temperature, humidity, microbial community, composition and structure of materials, etc.
Common biodegradable materials include natural polymer materials such as cellulose, starch, protein, etc., as well as synthetic biodegradable polymers such as polylactic acid (PLA), polyhydroxyalkanoates (PHA), etc.
The emergence of biodegradable materials provides an effective way to solve the environmental pollution problems caused by traditional non-degradable materials, and has broad application prospects in many fields such as packaging, agriculture, medical treatment, and textiles.
Common biodegradable materials include:
Polylactic acid (PLA): It is obtained by fermenting lactic acid from renewable resources such as corn and sugarcane, and then polymerized. It has good mechanical properties and transparency and is often used to make food packaging, disposable tableware, etc.
Polyhydroxyalkanoates (PHA): It is synthesized by microorganisms, with various types and different properties. It can be used to make films, fibers, etc.
Starch-based plastics: starch is the main component and is blended with other degradable polymers. It is often used in plastic bags, lunch boxes, etc.
Cellulose and its derivatives: such as cellulose esters, cellulose ethers, etc., They have good biocompatibility and degradability.
Polycaprolactone (PCL): It has good flexibility and processing properties and can be used in the medical field and packaging materials.
Chitosan: obtained by deacetylation of chitin, it is used in biomedicine, food packaging and other fields.
These materials play the role of biodegradability in different fields to reduce the negative impact of traditional plastics on the environment.
In general, the cost of biodegradable materials is higher than that of traditional plastics.
Traditional plastics, such as polyethylene (PE) and polypropylene (PP), are relatively low in cost due to their large-scale production and mature industrial system.
However, biodegradable materials, such as polylactic acid (PLA) and polyhydroxyalkanoates (PHA), often involve more complex processes and technologies in the production process, and the acquisition and processing of raw materials may also be more complicated, resulting in higher production costs.
For example, the production of PLA requires specific fermentation and polymerization processes, and the price of its raw materials (usually corn, sugarcane, etc.) will also be affected by market fluctuations.
However, with the continuous advancement of technology and the expansion of production scale, the cost of biodegradable materials is expected to gradually decrease, and the cost gap with traditional plastics may also gradually narrow.
Biodegradable materials have the following advantages:
Advantages:
1. Environmentally friendly: It can decompose naturally under certain conditions, reduce long-term pollution to the environment, and reduce the harm of white pollution.
2. Renewable resources: Its raw materials often come from renewable resources, such as plant fibers, starch, etc., reducing dependence on limited fossil resources.
3. Reduce carbon emissions: Carbon emissions during the production process are usually lower than those of traditional plastic manufacturing.
4. Widely used: It can be used in packaging, agriculture, medical care, textiles and other fields.
5. In line with the concept of sustainable development: It helps to promote sustainable economic development and meets the social requirements for environmental protection.
However, biodegradable materials also have some disadvantages:
Among them, kraft paper is one of the most widely used biodegradable materials in packaging.
Kraft paper is generally made of wood pulp, and its main component is cellulose. Cellulose is a natural organic substance that can be decomposed and metabolized by microorganisms.
Under appropriate environmental conditions, such as sufficient humidity, oxygen and microorganisms, kraft paper will gradually decompose into simpler compounds and eventually return to nature.
However, the degradation rate of kraft paper may be affected by many factors, such as the thickness of the paper, the treatment method (whether it is coated or other chemicals are added), and the environmental conditions.
But in general, compared with many synthetic materials, kraft paper is relatively easy to biodegrade in the natural environment.
As a packaging material, kraft paper has the following wide application scenarios:
1. Food packaging: such as the packaging of dry foods such as nuts, tea, and bread. Its good air permeability and certain moisture resistance can keep the food dry while reducing the impact of external odor and moisture.
2. Clothing packaging: used to wrap clothing, it can protect clothing from dust and slight friction.
3. Electronic product packaging: packaging some small electronic products such as headphones, chargers, etc., to provide certain buffering and protection.
4. Book packaging: whether it is the transportation protection of new books or the packaging of second-hand books, kraft paper material can be adopted as the packaging.
5. Gift packaging: due to its rustic appearance, it gives people a sense of simplicity and style. Thus it is suitable for packaging various gifts.
6. Industrial parts packaging: such as small mechanical parts, hardware accessories, etc., it can prevent collision and corrosion during transportation and storage.
7. Cosmetic packaging: Some minimalist cosmetic brands will choose kraft paper to package products, highlighting the concept of environmental protection and nature.