Uses and Production of Polypropylene
What is Polypropylene? What are the uses of Polypropylene? Polypropylene (pp) is a thermoplastic polymer produced through chain growth polymerization from the Monomer propylene.
Formula of Polypropylene:
The chemical formula of polypropylene is (C3H6)n
Properties of Polypropylene:
• IUPAC Name: The IUPAC Name of polypropylene is
Poly(1-methylethylene).
• Other names includes:
Polypropylene can also be called any of the following:
Polypropylene; Polypropene;
Polipropene 25 [USAN]; Propene polymers;
Propylene polymers; 1-Propene; [-Ch2-Ch(Ch3)-]n
• Density: The density of polypropylene is ;
0.855 g/cm3, amorphous
0.946 g/cm3, crystalline
• Melting Point: The melting point of polypropylene is 130 to 171 °C (266 to 340 °F; 403 to 444 K).
Production of Polypropylene:
Polypropylene production takes place by slurry, solution or gas phase process, in which the presence of a catalyst system subjects the propylene monomer to heat and pressure. Polymerisation can only be carried out at relatively low temperature and pressure and the product it yields is translucent, but readily coloured.
In the presence of a catalyst system, usually Ziegler-Natta or metallocene catalyst and the polymerization of propylene gas polypropylene is formed. Polymerization conditions such as reactant concentrations, pressure and temperature are set by the polymer grade to be produced.
Uses of Polypropylene:
The combination of propylene monomers produces polypropylene (PP), and it is a thermoplastic “addition polymer” . It is used to make packaging for consumer products, plastic parts for various industries including the automotive industry, special devices like living hinges, and textiles.
The most widely used general-purpose grade is the polypropylene homopolymer. In a semi-crystalline solid form it contains only propylene monomer. It is used for packaging, textiles, healthcare, pipes, automotive and electrical applications.
Advantages, Disadvantages and Uses of Polypropylene:
Advantages:
Polypropylene has so many benefits which have made it such a recommended type of material for manufacturers who can apply it to many uses. Here are some of the advantages of polypropylene.
1. Polypropylene is the ideal material for containers made to hold acidic liquids such as cleaning agents because it does not react with acids.
2. Polypropylene is the best material for piping systems because it is highly resistant to corrosion and chemical leaking. Climate conditions are not an issue to polypropylene pipes because the plastic resists to freezing well.
3. At it’s melting point polypropylene will turn to liquid, and in this form, it can be moulded into any desired shape, and this can be done several times without much degradation to the plastic. Polypropylene is also used in injection moulding because of the way it responds to heat.
4. Polypropylene is classified as an insulator because it does not conduct electricity well. This has made it an excellent material for manufacturing electronic components such as cables and audio equipment.
5. Polypropylene absorbs less than 0.01% of water when soaked in it, thud it is said to be impermeable. This makes it excellent for products which are dipped into liquids or items which need waterproofing.
6. Polypropylene can be made into a living hinge (a piece of material which can bend without breaking even after repetitive bending) because it is malleable.
7. Polypropylene is a useful material for heavy loads because it has high tensile strength, and it can withstand 4800 psi.
8. It also has a low density when compared to other plastics, so for manufacturers, they have the so much benefit of saving money from low weight.
Disadvantages:
1. Polypropylene has some dangerous sides which both the users and manufacturers should be aware of before they make use of the plastic material.
2. UV degradation affects polypropylene, making it unsuitable for use in high altitude or places where there is high UV penetration.
3. Polypropylene suffers from chain degradation which can lead to oxidisation when use in high temperatures. This causes cracks appearing in the polypropylene but can it be fixed with polymer stabilisers.
4. Polypropylene is a hard material to paint because of it’s poor bonding properties. The best solution for this is to treat the surface to enhance the adhesive strength of paints and inks which can colour the polypropylene.
6. Polypropylene will melt when exposed to heat because it is very dangerous and highly flammable. The flash point, a temperature which the liquid produces flammable vapour to form a mixture which can be ignited when contacted with a spark or flame, is just 260 degrees Celsius.
That’s all for polypropylene, drop your views in the comment section, also feel free to contribute your own perspective in the comment section.
