Polypropylene (PP) is a heavily used for injection molding and comes in the form of pellets. PP is a thermoplastic polymer made from the combination of propylene monomers. It is used in a variety of industries and applications such as household plastic items, living hinges, automotive parts, medical devices, plumbing, etc. Its extensive use has projected that demand will rise from 45 million to approximately 72 million metric tons by 2022.

Advantages of PP

Disadvantages of PP

PP Specifications

Melt Temperature160°C (320°F)
Typical Injection Mold Temperature32 – 66 °C (90 – 150 °F) *
Heat Deflection Temperature (HDT)100 °C (212 °F) at 0.46 MPa (66 PSI) *
Flexural Strength41 MPa (6000 PSI) *
Tensile Strength32 MPa (4700 PSI) *
Specific Gravity0.91
Shrink Rate1.5 – 2.0 % (0.015 – 0.02 in/in) *

*At standard State