The Italian scientist, Giulio-Natta, discovered PP properties in the mid-1950s when high density polyethylene (HDPE) was invented. The unique chemical configuration of PP rapidly revealed its high strength and became a superpower in plastic industry. The use of PP with high flexibility and lack of cracking increased its reputation and production capacity.
Semi-crystalline PP is a very successful product in most industries. Commercial production of PP was started in 1957 and had the highest industrial growth in recent years.
Like other thermoplastics, PP recycling caused a wave of happiness among environmental activists.
PP is synthesized in solution or gas phase. Propylene is polymerized at a certain pressure and temperature in the presence of Ziegler-Natta catalyst. PP properties vary with changing catalyst and operating conditions.
Propylene is the monomer for synthesizing polypropylene. PP is a linear hydrocarbon polymer which can be polymerized with syndiotactic, atactic and isotactic tacticities. Only the isotactic type with superior properties can be supplied to the market. Due to multiple and widespread applications, PP is among multi-purpose polymers in the plastic industry.
The smooth internal and external surface is among unique features of PP pipes. This facilitates fluid flow in such pipes. PP pipes are often thermal and sound insulators. Therefore, the flow of fluids such as water in PP pipes is not associated with noise. Also, hot water pipes will not cause damage to other devices.
Rusting of metal pipes change taste of drinking water in the pipe. In addition to rusting, sedimentation inside metal pipes causes many problems and provides conditions for the growth of algae and various types of fungi. PP pipes, however, are anti-algae and do not change water taste and color. So PP pipes are more used in domestic water pipelines.
PP pipes with a long lifetime of over 50 years are able to reduce executive costs in urban and industrial facilities without degradation. PP pipes are also easily transported. Due to lightweight and resistance to pressure, PP pipes can be buried under ground and used for many years.
PP pipes are highly durable due to lightweight, weldability and abrasion resistance. PP pipes are also good thermal and electrical insulators. High temperatures up to 90 ̊C do not negatively affect PP pipe structures in long term. In addition, temperature rise up to 110 ̊C in short term does not affect PP structures. Excellent chemical resistance to aqueous, acidic and basic solutions, salts and most organic solvent leads to widespread application of PP pipes.
PP pipes are heated by fusion welding. PP pipes are among lightweight plastic pipes with high resistance to chemicals.
Applications of PP pipes
- Chemical discharge systems
- Industrial processes
- Water transmission
- Hot and cold water distribution
- Wastewater systems
- Piping sub-fittings
PP pipe properties
- Semi-rigid
- Semi-transparent
- High chemical resistance
- Good abrasion resistance
- High thermal resistance