PP plastic, chemical name: polypropylene
Non-toxic, odorless, low density, strength stiffness, hardness and heat resistance are better than low-pressure polyethylene, can be used at about 100 degrees. It has good electrical properties and high-frequency insulation is not affected by humidity, but becomes brittle at low temperature. Not wear-resistant, easy to age. Suitable for making general mechanical parts, corrosion-resistant parts and insulating parts. Common acid and alkali organic solvents have little effect on it and can be used in food utensils.
2, molding characteristics
·Crystal material, low hygroscopicity, easy to melt fracture, long-term contact with hot metal is easy to decompose.
·Good fluidity, but the shrinkage range and shrinkage value are large, easy to shrink holes, dents, deformation.
·The cooling speed is fast, the pouring system and the cooling system should be slowly dissipated, and pay attention to control the molding temperature. The material temperature is easy to orient at low temperature and high pressure. When the mold temperature is lower than 50 degrees, the plastic parts are not smooth, and it is easy to produce poor welding and flow marks. More than the degree of warpage
·The plastic wall thickness should be uniform to avoid lack of glue and sharp corners to prevent stress concentration.