Polyethylene
Polyethylene,
was discovered largely by accident in 1933 by scientists working for ICI.
From 1937 pilot plant work proceeded but only a
small amount of polymer was produced. The first
plant came into operation in September 1939 and
the resultant product, named "Polythene"
by ICI, was to have a major impact on the war
effort. It was found that the long chain, low
density white polymer could be extruded as film
and coated around wires and cables to give
greatly enhanced performance. Polythene was a
superb insulator with high dielectric and low
loss factor and was thus in great demand for
submarine cables, radar applications, etc.
Major production continued from 1942 and ICI
licensed other companies thereafter in the
production of high pressure polyethylene which
produced the low density product - LDPE. However,
the extreme conditions and costs for production
coupled with low temperature softening, creep and
stress cracking of LDPE limited the full
potential of the polyethylene family of polymers
in film blowing and injection moulding volume
applications.
The development of new improved conditions for
manufacture and control of molecular structures
was to create accelerating and dramatic changes
in the growth of polyethylene and other
polyolefin polymers. (See Karl Ziegler and Giulio Natta)
The subsequent huge range of products, especially
in packaging films and containers coupled with
great design and production flexibility through
controlled material properties, has affected
almost every aspect of modern life.
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