Short Introduction To Polyethylene: One Story, A Thousand Uses

As many brilliant inventions, polyethylene was born bywrap. Polyethylene is commonly used not only to
chance, thanks to a lab accident in 1898 caused bycover electrical wires, but also wooden panels, as a
Han von Pechmann, a German chemist who wasgood alternative to the paint (think of airplane
heating diazomethane in a holder. In 1933, anothermodels). Therefore, the objects wrapped in
accident occurred, this time in an English factory, theheat-shrinking film hold together well protected,
ICI Chemicals, when Eric Fawcett and Reginald Gibsongranting a resistant and slim packaging, required in the
applied a pressure of hundreds of atmospheres to aproduction industry as well as in the food one.
holder containing ethylene and benzaldehyde. In bothSpeaking of types of polyethylene, its ultimate
cases, the scientists were impressed by the waxyevolution on the market is the stretch film. As the
material appeared in the holders. However, while inname states, it has elastic qualities, and it is especially
the first case they named it as polymethylenesuitable for the protection of goods stacked on
without investigating further, in the second theypallets or sensitive to the hot, which would be
spent years trying to recreate it again, without anydamaged by the thermo retraction.
success.As a consequence, the main employment of
The turning point occurred in 1935, when not anpolyethylene is in the film packaging domain: the
accident, but the will of another chemist, Michaelprotection wrapping goods is, once again,
Perrin, finally obtained polyethylene. Its electricalpolyethylene, like the plastic used to pack suitcases.
insulation property was soon recognized and, in 1939,The multiple qualities of this material, insulating,
began the industrial production of plastic films: sincewaterproof, heat-shrinking and resistant, in spite of
then, polyethylene rolls became an essential supplyits thickness, more and more thinner (think of the
for any production department, requested by a wideplastic wrap for food, which thickness is measured in
range of companies, from food packaging tomicrons), let us imagine a thousand different uses.
electrical wires production.Lastly, polyethylene has a further quality: it is a
Furthermore, polyethylene is a thermoplastic material.recyclable material. Both production wastes, such as
This means that if its temperature is increased, ittrimmering of the rolls, and used polyethylene sheets
changes state and becomes viscous and malleable:can be recovered to produce a low price packaging
heat-shrinking film was the next step. During thewith an high environmental value. An opportunity
production stage it is possible to shape it as desired;today even more important, as we know that, at
the user must then heat it with hot air, a flame or anthe base of polyethylene, there is the shortage and
oven to shrink it up to the 50% of its volume andthe inconstant price of oil.
make it adhere perfectly to the object needing a