Material is an important determinant of product performance, quality, price, and scope of application. To improve the comprehensive performance of the seven-layer coextruded film, it is necessary to understand the following materials:
1. For PE materials, because there are many PE product brands, LLDPE is SK FV149, LDPE is Shanghai Petrochemical Q281 and Q200, or C8LLDPE is used in heat sealing. FV149 + EVA blended materials are more. Combined with the up-blowing method, it can increase the flexibility and dimensional stability of the seven-layer coextruded film, while also improving the transparency.
2. Nylon materials, currently used for the production of seven-layer co-extruded nylon film is mainly imported materials, the main suppliers are DSM, BASF, DUPONT, Mitsui, Toray, Mitsubishi, etc. The most commonly used materials are BASF's B36LN, B40, DUPONT's Selar PA, etc. In the selection of nylon materials, one or two materials cannot be fixedly selected, and should be selected and matched according to the specific use of the product. For example, in the casting method, if the hot stretch forming cover film is produced, in order to maintain the dimensional stability of the film during use and eliminate the curling phenomenon, SelarPA20% + homopolymerized PA can be used as the outer layer PA material.
3. TIE, the data shows that the TIE material of the seven-layer coextruded film is the most used by DUPONT 30E671. Of course, there are other brands of products that can be replaced, such as SK's LE350V.
In addition to ensuring the correct selection of the above materials, the parameter design of the seven-layer co-extruded film in the mechanical production process should also be considered, such as the temperature setting of the extruder!