Polypropylene is a thermo-plastic polymer which has a wide usage field from the parts used in automotive industry to the textile and food packing. The polypropylene which is gained by making monomer propylene as polymer is terribly resistant to chemical solvents (acid and alkalis).
The most common commercial polypropylene has got a level between the polyethylene (LDPE) whose crystal shape is low density and HDPE whose crystal shape is high density. Young module (elasticised module) is at the middle level, too. Nevertheless, it is less harder than LDPE and much less crispier than HDPE. This allows polypropylene to be used for the engineering plastics such as ABS.
Polypropylene has a very good resistant to wearing. It is low costly and has got a good stroke resistance. The friction coefficient is lower and gives good electricity isolation. Its chemical resistance is good. It is suitable to all of the thermo-plastic processes. The melting temperature of the polypropylene is around 160°C.
In spite of that, it has such disadvantages: it has less UV gleam resistance. It shows high thermal dilatation. It is hard to paint and cover it. The resistance to outside weather conditions is less and open for oxidation. It is flammable and interacts with the solvents containing chlorine.