1. The combination of different polymers meets the requirements of oxygen and moisture protection for packaging materials, usually composed of 4 kinds of polymers, but seven, nine, eleven or even more layers of co-extrusion have also appeared on the market Composite membrane. Among them, the co-extruded composite film with PA and EVOH as the intermediate barrier layer has developed rapidly and has a large output. As a result, it is not difficult to see that its characteristics are strong air barrier performance, oxidation resistance, water resistance, and moisture resistance.
2. Strong mechanical properties, high blast resistance, strong puncture resistance and tear resistance. It can be used in industrial products for anti-oxidation and anti-corrosion packaging of welding materials, electronic products, circuit boards, etc., precision mechanical parts, etc.
3. High temperature resistance around 121℃, low temperature resistance around -50℃, good oil resistance and fragrance retention performance. Can be applied to vacuum food packaging, such as rice, meat products, dried fish, aquatic products, cured meat, roast duck, roast chicken, roast pig, frozen food, ham, cured meat products, sausages, cooked meat products, pickles, bean paste, The flavor, quality, taste and color of seasonings.
4. Non-toxic and tasteless, in line with food and drug packaging hygiene standards. Can produce high barrier packaging film, shrink film, vacuum cling film, geomembrane, etc., can be widely used in food, medicine, daily chemical product packaging, agricultural greenhouse film and other fields, geomembrane can be used in water conservancy engineering, environmental engineering and other fields .
5. Good heat-sealing performance, flexibility, and high transparency. Using multiple layers of the same polymer instead of single-layer polymer in the barrier layer can improve the stability of the barrier layer.
6. Multi-layer co-extruded composite film mostly adopts ABCBA five-layer symmetrical structure and seven-layer, etc., with PA or EVOH as the barrier layer, and PE as the heat-sealing layer. From the perspective of its functional combination, there are mainly three functions of barrier, heat sealing and bonding.
7. Multi-layer co-extrusion film technology uses more than three extruders to extrude several different resins and enter the die for compound co-extrusion to obtain film products with certain functions. Commonly used symmetrical structures include PE/Tie /PA/Tie/PE.
8. The main features of multi-layer co-extruded film are economy, functionality, and high strength. For example, pvdc has a high barrier to oxygen and water vapor, but its price is high, and the mechanical strength of the film is poor. Therefore, the use of pvcd and ldpe, hdpe, lldpe and other materials co-extruded and blown film, not only meets the barrier properties, but It meets the necessary mechanical strength for packaging, is cost-effective, and has high market competitiveness. It is the best choice for fresh meat and ham packaging.
9. When it is confirmed that the thickness of the barrier layer set is sufficient to meet the barrier requirements, replace the single-layer polymer with multiple layers of the same polymer in the barrier layer, which can reduce the cost of high value-added raw materials for the barrier film.
10. Integrate the functions of dry-type composite film except for printing, simplify the composite process, the composite structure tends to be flexible, the function tends to be diversified, the cost is significantly reduced, and it is more in line with the requirements of health and environmental protection, social benefits and economics The benefits are more significant.
11. The use of two different polymers in the barrier layer to replace a single type of polymer can significantly improve the barrier properties of the film and prevent the outer barrier film from being easily damaged by external forces and resulting in a decrease in the barrier effect.