Why polyethylene is the most common plastic in the world?
Because the annual production of polyethylene is approximately 80 million tonnes per year, and this is a lot.
Another reason is that polyethylene has countless applications, some of them are foils, bags, films, membranes, containers, bottles, pipes etc.
To understand better what is polyethylene you need to know the chemical formula which is this (C2H4)n or this:
Polyethylene is also called polythene or poly(methylene) and the abbreviated is PE.
PE is usually a mixture of similar organic compounds that differ in the numbers of value of n in our chemical formula (C2H4)n.
How did this very popular material appear in our world?
Let’s have a look on its very interesting history.
In 1898 a German chemist, Hans von Pechmann heated diazomethane (he also discovered it) and by accident he obtained polyethylene. Then Eugen Bamberger with Friedrich Tshirner worked on the features of the substance that Hans had received. They found that this white and waxy substance is a long particle, which contains -CH2– chains and they called it polymethylene.
In 1933 in England, Eric Fawcett and Reginald Gibson discovered a first industrial polyethylene synthesis, also by accident. This reaction was more stable than the previous one. They applied extremely high pressure (several hundred atmospheres) to a mixture of ethylene and benzaldehyde and they again made a white, waxy material, which was PE. The experiment was difficult to reproduce because the reaction had been initiated by oxygen contamination in their equipment.
In 1935, another chemist Micheal Perrin, recreated the above case into a reproducible high-pressure synthesis. This reaction became the basis for industrial low density PE production, which started in 1939.
Polyethylene was found to have very low-loss properties at very high frequency radio waves. Commercial distribution in Britain was delayed because of World War II but production was running secretly. The product was used for insulation for UHF and SHF coaxial cables of radar sets.
During World War II, research progressed in the Imperial Chemical Industries laboratories. In 1944 Bakelite Corporation at Sabine, Texas, and Du Pont at Charleston, West Virginia, started a large scale commercial production of PE under license from the Imperial Chemical Industries.
In the end, PE is nothing but an accident.
PE is very special polymer, which has many applications, but why it is so popular we will find out next time.