On the other hand it does not stand up well to abrasion and atmospheric agents. It is a semi-crystalline thermoplastic material, like PE, but is more resistant and rigid and melts at a higher temperature despite having a lower density. It is a thermoplastic, semi-crystalline material like PE, but is tougher and more rigid and melts at a higher temperature although having a lower density. Thanks to its non-polarity characteristic, PP is highly resistant to chemicals: it retains its resistance to aqueous solutions containing salts, and strong acids and alkalis in temperatures up to + 120ºC. Yet, at ambient temperatures it is susceptible to attack from strong oxidising agents such as nitric acid and halogens.
It is available in formulations that improve its resistance to fire (self-extinguishing PPs). Talcum is one of the fillers most commonly used in PP. It improves its rigidity, dimensional stability, its resistance to heat and ability to slide; in addition it acts as a nucleating agent. The disadvantages associated with it are a reduction in its resistance to impact at low temperatures, the reduction of its weldability and its resistance to oxidation at high temperatures, and the formation of a more opaque surface.
Engineering, aerospace, chemical, electrical and building sectors.
Examples: tanks, plant components, fans, parts for submerged pumps, rings, flanges, pulleys and gears.