The polymerization of propene produces the thermoplastic polypropylene (PP). It is a semi-crystalline polyolefin.
PP behaves very similar to PE, but is harder and more heat resistant.
With 0.89 – 0.92 g/cm³ PP has the lowest density, compared to the standard plastic materials.
The operating temperatures are between 0 and 100 °C.
The fatigue resistance is very high, therefore PP is well suited for use in hinges.
All these features make PP one of the most important plastics in the world today.
Even synthetic fiber production is largely based on PP.
Polypropylene is used primarily in packaging.
Further fields of application are household appliances, toys, sporting goods and agricultural equipment.
It has to be noted that PP is not very suitable for gluing and painting.