PP is a thermoplastic material closely related to low-pressure PE, but it has a lower density and is more rigid, harder and more heat-resistant. It is a thermoplastic (moldable) plastic. With a 20% share of total plastic production, it is the second most important plastic after polyethylene (PE). Polypropylene can be used at temperatures from around 0 °C to 100 °C.
Originally, the material was mainly processed using injection molding. Today, extrusion is another important processing method.