Views:220 Author:Site Editor Publish Time: 2019-12-09 Origin:Site
PP is a thermoplastic resin. Like PE, it can be processed by all processing methods of thermoplastics. Extrusion, injection molding, blow molding, lamination, casting, biaxial stretching, powder spraying, foam molding, etc. can be used. Extrusion, injection molding, and blow molding are commonly used molding methods.
The MFR of PP for extrusion molding is relatively low, and the molding temperature is between 180 and 260 ° C. Films, pipes, rods, plates, profiles, single wire, flat wires, wire and cable coatings can be made by PP sheet extrusion machine. Due to the low density and high melting point of PP, the length of the feeding section of the extruder screw is generally longer than that of PE;
About half of the PP products are produced by injection molding, and most of the copolymerized PPs have high impact strength and low embrittlement temperature. The injection molded PP generally uses medium molecular weight, with a melt flow index of 3 ~ 4.5g / (10min). It is suitable to use a high melt flow index PP for manufacturing complex shapes and thin wall products. The injection temperature is 200 ~ 275 ℃, the pressure is related to the injection equipment, the screw type injection molding machine is lower, and the plunger type is higher;
Blow molding includes injection molding and extrusion molding. The difference is that the manufacturing method is different. The blow molding process is the same. Blow molding is mainly used for the production of films and hollow containers. The bottom MFR resin is generally used.