A

These are generated by unmelted particles if kneading is bad in the extruder. Lower the extrusion speed or replace the screw for one with better kneading. There are also generated due to the mixing of impurities when regenerated resin is used. Regularly clean the silo, transport path, hopper, screw, and die.

A

MI is also called MFI (Melt Flow Index). It is measured according to standard testing methods such as ASTM D1238, and is defined as the weight of the resin flowing in the molten state through an orifice under the temperature and load conditions specified in the standard for 10 minutes (unit: g/10 n.).  MI is directly related to the molecular weight and viscosity of the polymer product. High MI improves processability, but somewhat more lacking in properties like stiffness and impact resistance.

A

PP is categorized by homo PP and impact PP according to the polymerization state. Homo PP is produced by chaining propylene monomers, while impact PP is produced by adding ethylene (rubber phase) to homo PP. Although homo PP features excellent stiffness, its impact resistance is weak at low temperatures. Impact PP reinforces the impact resistance at low temperatures, but it is not as stiff as homo PP. You can select the product that meets your usage requirements.

A

PP processing temperatures vary widely according to product characteristics and processing mode. However, it must be higher than the melting point of PP, which is about 165°C, and processing at temperatures of 250 °C or higher can cause adverse effects on product appearance due to carbide, etc. It is typically processed between 200 and 230 °C. 

A

You can view the product properties of PP from GS Caltex on the website where the products are introduced. Please contact the Polymer Technology Development Team (+82-42-866-1671~5) if you need more detailed information.