What are the differences in extrusion characteristics of different types of materials in Screw Barrel?

There are significant differences in the extrusion characteristics of different types of materials in Screw Barrel, which are determined by their unique physical and chemical properties, as well as the specific process conditions required. This difference makes it necessary to finely adjust the operating parameters of the Screw Barrel for different material types in the actual production process to ensure the smooth extrusion process and stable quality of the final product.

Plastic is a type of material widely used in the production of cast films, with a wide variety of types including polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), etc. The extrusion characteristics of these plastic materials in Screw Barrel vary due to their melting temperature, fluidity, and thermal stability. For example, PE has good fluidity and is easy to plasticize during extrusion, but may require higher temperatures and pressures to ensure complete melting. In contrast, PP has a higher melting temperature and requires higher temperature and longer melting time during the extrusion process. Due to its poor thermal stability, PVC must strictly control temperature and speed during extrusion to prevent thermal decomposition.

There are significant differences in physical and chemical properties between rubber and plastic, resulting in different extrusion characteristics. Rubber materials usually have high viscosity and elasticity, which requires higher shear force and temperature during the extrusion process to achieve good fluidity. In addition, due to the slow extrusion speed of rubber, special attention needs to be paid when operating the Screw Barrel to avoid generating too much heat and shear force, which can lead to material degradation.

In addition to plastic and rubber, thermoplastic elastomers (TPE) are also a commonly used material in the production of cast films. TPE combines the elasticity of rubber with the processability of plastic, and its extrusion characteristics fall between the two. This requires the extrusion process of TPE in Screw Barrel to consider both the melting and flowability of plastics, as well as the viscosity and elasticity of rubber. Therefore, when extruding TPE, it is usually necessary to carefully adjust parameters such as temperature and pressure to achieve the desired extrusion effect.