The hottest multilayer film protects sensitive foo

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Through this article, BASF (BAS quantity) will reveal the materials used in flexible packaging and their advantages. Headquartered in Ludwigshafen, Germany, the company is one of the world's leading plastic manufacturers. She also provides polyamide (PAS), the main starting material for the production of synthetic films. Polyamide is made of uitramid a, B and C series materials

nowadays, 90% of food arrives at customers in a packaged state. Most of these packages are made of plastic, which has many advantages. Usually, these packages should be strong enough to avoid damage in the shopping bag and easy to open when in use. Because most of today's customers don't have much time to go shopping often, food such as sausage, cheese, fish and so on should not only be kept fresh for a long time in the state of packaging, but also be preserved completely to ensure that people have a good meal

demand remains high

the demand for packaging materials remains quite high. At the same time, the requirements for product characteristics are also quite high, including high strength, high flexibility, and the ability to prevent odor, oxygen, carbon dioxide, water vapor and other gases from penetrating. At present, many foods cannot attract shoppers, so advanced packaging should not only preserve food for a long time, but also attract customers' attention

how to achieve this function will really confuse ordinary people. Behind this real transparent plastic packaging, there are surprisingly complex technologies. Dr. Egbert gr ü tzner, r0l quantity of BASF's high-performance polymer department, said: "there is no universal plastic that can meet all requirements. Only after synthesizing different materials with different properties, can it meet the requirements of more applications."

information about PE, PP and PA

polyethylene or PE is currently mainly used in the manufacture of films and containers. This material can completely prevent the penetration of water vapor, but it cannot prevent the penetration of other gases such as oxygen or carbon dioxide. This material has the properties of preventing acid, alkali and other chemicals. PE is the most produced plastic in the world, accounting for 30% of the total global products

polypropylene, or PP, is very similar to PE. Its main components are also carbon and hydrogen. The properties of PP are similar to those of PE, but they are harder, stronger and more brittle than similar materials

The structure of polyamide or PA is more complex. It contains not only carbon and hydrogen, but also oxygen and nitrogen. Because of its unique performance, it has a wide range of successful applications. For example, as a general-purpose basic material used in hairstyle products, steel mills may face production restrictions, muscle products and enzyme products, but also used in industrial fields. In addition, the filament produced with nylon fiber has a history of 60 years to avoid high-voltage damage to the test object and even harm to the human body. PA is powerful and can be applied to multilayer films, mainly to prevent oxygen and chemicals, and can play its function normally even at high temperature

use of these materials

the synthesis of these new materials is completely based on the characteristics and requirements. In most cases, PE or PP is mainly used as the basic material of multilayer films. They have good flexibility, water vapor prevention and good sealing properties. Because of these good characteristics, PE film has been successfully used in household food film packaging for a long time. However, if the requirements are more stringent, it is usually preferred to synthesize with PA. Because PA has properties that PE and PP cannot. PA is stronger and more flexible, which can keep oxygen and carbon dioxide, and maintain its original shape even at high temperatures. According to the needs of use, these basic materials can be added with protective supplementary materials, such as ethylene vinyl alcohol copolymer (EVOH), adhesives, adhesives, etc. to bond different layers. At the same time, in order to ensure the beautiful appearance, exquisite patterns can be printed on the outer layer, or a layer of aluminum film can be coated to avoid light and protect food

typical applications of these synthetic materials include the popular dish packaging, which is very attractive for sausage and cheese slices. In addition, you can also make solid thermoformed low plates. For example, a layer of PP and a layer of PA are bonded with adhesive: the film cover with good flexibility, which can be torn in layers and sealed repeatedly can be synthesized with PE and BOPA; More powerful is pa made of uitramid B of BASF. Gr ü jtzner explained that "BOPA stands for biaxially stretched polyamide (also known as Biaxially Stretched Nylon). In other words, it is also a PA film, but the molecular chain structure of the internal polymer is highly organic." Because of its high tensile strength, BOPA film can be made into ultra-thin film, which can still maintain very high strength. BASF's plastic expert stressed: "without innovations like BOPA, we cannot meet the growing needs of consumers and industry, which is much smaller than the clamping force of the traditional high-pressure injection process."

map function

the new generation of zigzag strength>205 MPa durable packaging materials are busy with advanced packaging technology, such as modified atmosphere packaging (map), which is very ideal for use in combination. With this technology, the gas around packaged food can be replaced with protective gas, such as nitrogen or other inert gas, or the mixture of nitrogen and carbon dioxide. The regulated gas can slow down the speed of oxidation, inhibit the growth of microorganisms and prolong the life of products. All of these do not need any preservatives. However, the packaging materials must ensure that the effectiveness of gas prevention must be maintained to the required time limit, otherwise the protective gas will disperse rapidly

although there is such profound technology behind today's non talking packaging bags, the cost of technology only accounts for a very small share of the product sales price. At the same time, because the use of such materials can produce thinner films and save materials, it not only creates benefits for manufacturers, but also provides very obvious advantages compared with traditional materials such as glass, cans, coated paper, such as environmental protection, good economic benefits, etc


in addition to the above advantages, there are many benefits. The way of life in our times is changing. For example, there are more and more single families, there is no time to cook, and the single life cycle is getting longer and longer. These changes will stimulate the further development of this market. The annual global packaging trade volume is 3.200 billion packages, of which flexible plastic packaging accounts for 26%. The market growth rate this year is expected to reach within the range of 2-4%. (end)

source: plastic industry

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