Because the reaction had been initiated by trace oxygen contamination in their apparatus, the experiment was difficult to reproduce at first. Upon applying extremely high pressure (several hundred atmospheres) to a mixture of ethylene and benzaldehyde they again produced a white, waxy material. The first industrially practical polyethylene synthesis (diazomethane is a notoriously unstable substance that is generally avoided in industrial application) was again accidentally discovered in 1933 by Eric Fawcett and Reginald Gibson at the Imperial Chemical Industries (ICI) works in Northwich, England. Polyethylene is usually thermoplastic, but it can be modified to become thermosetting instead, for example, in cross-linked polyethylene.Ī pill box presented to a technician at ICI in 1936 made from the first pound of polyethylene It can be low-density or high-density: low-density polyethylene is extruded using high pressure (1,000–5,000 atm (100–510 MPa)) and high temperature (520 K (247 ☌ 476 ☏)), while high-density polyethylene is extruded using low pressure (6–7 atm (610–710 kPa)) and low temperature (333–343 K (60–70 ☌ 140–158 ☏)). PE is usually a mixture of similar polymers of ethylene, with various values of n. Many kinds of polyethylene are known, with most having the chemical formula (C 2H 4) n. As of 2017, over 100 million tonnes of polyethylene resins are being produced annually, accounting for 34% of the total plastics market. It is a polymer, primarily used for packaging ( plastic bags, plastic films, geomembranes and containers including bottles, etc.). Polyethylene or polythene (abbreviated PE IUPAC name polyethene or poly(methylene)) is the most commonly produced plastic.
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