24th March 1933. Polythene.
Polythene is the most common plastic and the Brand Name for Polyethelene (Polyethene) which resulted from experimentation Today in 1933.
Two organic compounds were heated to 170°c to a pressure of 1700 atmospheres by two Imperial Chemical Industries (ICI) scientists, Reginald Gibson and Eric Fawcett, but they later found that instead of the Ethylene and Benzaldehyde combining as expected, a white, waxy solid was left.(1)
It was then demonstrated that this was a Polymer of Ethylene (Ethene) (C2H2 or H2C=CH2) that could be melted and drawn into threads of varying lengths of polymer chains of Ethylene units.
Ethylene is the most widely used of any organic compound and much of it to produce Polyethylene plastic, which under the Brand Name Polythene was first manufactured in 1948.(2)
The apparatus used in 1933 was presented by ICI to The Science Museum on the 50th anniversary of the first experiment.
There is a plaque commemorating the discovery of polythene in 1933 at Winnington (Northwich) Cheshire the former Brunner Mond (ICI) laboratories built in 1873.
The plastic fibres were derived from fossil fuels, coal and oil in the 20thc and created by companies such as Courtaulds and ICI.
Polythene was to join Polystyrene, Polyester, PVC and Nylon, but all posing problems of decomposition. The future lies with bio-derivatives from the likes of sugar-cane.
(1) Benzaldehyde consists of a Benzene ring with a Formyl substituent and is the simplest aromatic Aldehyde and one of most industrially useful.
Benzaldehyde and similar chemicals occur naturally in foods such as almonds, apricots, apples and contain Amygdalin.
(2) Ethylene is a colourless flammable gas with sweet musky odour and is the simplest of the Alkene Hydrocarbons with C-C double bond.
Ethylene is a natural plant hormone and ripens fruits and its hydrate is Ethanol.