PP plastic ball (polypropylene) English name: Polypropylene 0.9-0.91 g / cm 
 Mold Shrinkage: 1.0-2.5% 
 Forming temperature: 160-220 ℃ 
 Dry conditions: the development of polypropylene is the second after another fine nylon resin varieties, it is a high density, no side chain, linear polymers of high crystallinity will, with excellent overall performance. When not colored white translucent, waxy; lighter than polyethylene. Are more transparent polyethylene better than polyethylene rigid. 
 Material properties density, strength stiffness, hardness, heat resistance are superior to low-pressure polyethylene, can be used at 100 degrees has good electrical properties and high-frequency insulation from humidity, but the low temperature brittle, do not wear easy to aging. for production of general machinery parts,