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The profits from Polypropylene can get around USD 145 bilion in 2019. Why can this simple polymer make such a lot of money?

If we want to understand the phenomenon of polypropylene is important to know that polypropylene is very different from the other polymers. The features of polypropylene allow it to be effective material for everyday use products where price, non-staining and non-toxic solutions are required.

Polypropylene, polypropene or PP is a thermoplastic polymer, and it is used in a variety of applications such as:


stockvault-power-cables-close-up111016 Bottles
cable insulation chemical tanks
automotive parts

like bumpers (very large business)

carpet fibers

And also packaging and labelling, textiles, plastic parts, reusable containers, laboratory equipment, gas cans, battery boxes, bottles, petrol cans, indoor and outdoor carpets, loudspeakers and thermoplastic fibre reinforced composites.

What makes polypropylene a great product?

We already know that PP is cheap, non-staining and non-toxic. It is also resistant to a wide range of chemical solvents, bases and acids and in higher temperature it is dissolving in aromatic hydrocarbons or esters.

Its density is one of the lowest among others popular polymers, it is 0.855 g/cm3 for the amorphous and 0.946 g/cm3 for the crystalline type.It does not absorb water like other plastics, moreover it is lightweight, transparent and very flexible. It is also physiologically neutral, flammable and odour-free.

Polypropylene has also an excellent temperature range where can be used. Polypropylene has a high melting point 130 – 160°C (266 – 320F) if we compare it to similar plastics and this works very well for food containers where high temperature matters (microwaves and dishwashers).

It is easy to manufacture, too. The desired shape of PP can be easy achieved by Extrusion Blow Moulding, Injection Moulding, and Extrusion. If we want to avoid the polymer degradation, it is important to not pass 270 °C (518F). It is important that PP can be colored during the manufacturing process without changing the quality of the product.

Polypropylene does not contain BPA and can be used in contact with food. BPA is not safe for food contact and it has been linked to health issues, especially in children.

As PP has a low level of electrical conductivity, it is highly effective in electronic products.

Polypropylene structure

Polypropylene is stereoisomeric, this means that one carbon atom in every unit is the chiral centre. This gives a possibility to create three stereoisomeric forms and the consequence is that the melting point and the crystallinity depends on the stereoisomeric type of PP.

Isotactic Polypropylene

The most commercial form of polypropylene is the isotactic type which has the greatest mechanical properties and the highest melting point 160-166oC. It obtains a medium level of crystallinity. If we compare isotactic polypropylene to polyethylene,we can say that PP is more inflexible, tear resistant and has more bonding.

Syndiotactic Polypropylene

The syndiotactic type, with 30% of cristallinity, has weaker mechanical properties than the isotactic type and also the melting point is lower 130 oC.

Atactic Polypropylene

The atactic type of polypropylene has the weakest mechanical properties and because of that it is not used as a construction polymer.

Market Prices:

In the market there are three available types of polypropylene: homopolymers, block copolymers and random copolymers.

Below you can see some websites where you can forecast or find current prices;


We need to remember that PP is also not resistive to oxygen, therefore is necessary to use antioxidants as well as UV stabilizer as PP is not resistive to UV.