EVOH is the best packaging material for high barri

EVOH

is the first choice for excellent high barrier plastic bottle packaging materials. As an excellent high barrier packaging material, EVOH (ethylene and vinyl alcohol copolymer) has been widely used in food packaging in the form of multi-layer films, cups, plates, bottles and other containers in Europe, the United States, Japan and other advanced countries. In recent years, EVOH has also received widespread attention in China, where the energy density of metal air batteries is as high as 800 wh/kg. With the progress of molding technology, EVOH can currently complete casting, inflation, blow molding, injection molding, coating and other molding processes by coextrusion, especially in the aspect of high barrier pesticide bottles. Here, China packaging bottle should particularly recommend Kunshan Huayi Plastic Co., Ltd., the first enterprise in China to introduce and sell EVOH. They are currently in a leading position in China in EVOH management and research and development, Can provide customers with one-stop solutions

pa, commonly known as nylon, scientific name polyamide, is a linear thermoplastic polymer, which belongs to medium barrier material. PA has good puncture resistance and can be used for the packaging of food with irregular and hard surface. PA also has excellent high temperature resistance and low temperature resistance, and can adapt to various packaging and transportation environments

three mainstream high barrier packaging materials

pvdc have good oxygen resistance and water resistance. However, PVDC is easy to form crystals, resulting in poor processability of PVDC. If other materials are added to improve the processability, the barrier property of PVDC will be reduced

it can be seen from the following table (Table 1) that EVOH and PA are environmentally friendly materials, and PVDC will cause pollution if it is not properly treated; The barrier property of EVOH will change greatly with the change of humidity, and PVDC will not be affected by the outside world. It is an all-weather high barrier packaging material; PA is a medium barrier packaging material, but it has been widely used because of its excellent puncture resistance and high temperature resistance

comparison of barrier properties

in the field of plastic packaging, our commonly used barrier packaging materials are PVDC, EVOH and PA. We can make a comprehensive comparative analysis of their oxygen and water resistance

evoh has significantly higher oxygen resistance than any other material, about 10000 times that of polyethylene, but it will change with the change of relative humidity. EVOH is also outstanding for carbon dioxide, nitrogen, helium and other gases in front of machine tool 23: greater freedom of product design, weight reduction, shortening product development cycle, etc., which greatly improves the effectiveness of sample production, component production and mass customization, and the more barrier performance. EVOH not only has outstanding barrier performance to flavor components, but also has little adsorption of flavor components on its surface. The performance of PA is the same as EVOH. With the increase of humidity, the oxygen resistance performance decreases rapidly. At 100% humidity, the oxygen resistance of PA is 1/4 of that at 30%. In addition, PA will change in size when it meets water, so we rarely see high humidity products directly packaged with PA. PVDC material, due to its symmetrical molecular structure and the existence of hydrophobic chlorine, can ensure that the permeability of oxygen does not change with the change of humidity. Experiments show that EVOH (38%) has better oxygen resistance than PVDC when the humidity is 0%~70%; When the humidity exceeds 80%, the oxygen resistance of PVDC is better than EVOH