Polypropylene is an inexpensive semi-crystalline thermoplastic and belongs to the group of polyolefins. Compared to PE-HD, PP has a higher stiffness, hardness and strength. PP also has a slightly higher heat resistance than PE.
Semi-finished plastic products made of PP are also frequently used in chemical apparatus engineering at temperature stress between 0° C and +100 °C. The upper operating temperature is +100 to +110 °C. PP offers very good chemical and excellent hydrolysis resistance and low moisture absorption at low density
The stiffness of polypropylene combined with its good mechanical strength values, as well as its high surface hardness allow the design of molded parts or welded constructions with relatively thin walls.