Poly(vinyl
chloride)
Vinyl chloride was first
produced in 1835 by HV Regnault who also observed
its polymerisation by sunlight. Ostromislenski
investigated it further in 1912, and H Staudinger,
by fractionating the polymer from solution in
1930, was able to show the relationship between
polymer molecular weight and solution viscosity.
The polymer, however, was not commercialised
until Waldo Semon produced a plasticised material
in the 1930s, when it was introduced mainly as
unsupported, flexible sheeting. An early and
important use was as a waterstop in dam
construction.
The technique of producing PVC plastics from a
paste of polymer and plasticiser by gelling on a
hot surface originated in Germany in 1931, and
was commercially used in the UK from 1942. It was
also developted to make PVC coated materials for
upholstery by spreading the paste onto a fabric,
and also used to make hollow articles such as
squeaky toys and dolls. Such processes have been
known as slush moulding, rotational casting and
dip moulding.
Due to shortage of natural rubber during World
War II, PVC was employed as a rubber substitute
for cable covering and many other uses. PVC
stripped from unwanted cable after the war was
used to make the notorious 'plastic mac'.
Internal plasticisation by copolymerising vinyl
chloride with vinyl acetate was patented by EW
Reid in 1928 and was used to mould long-playing
and 45rpm gramophone records, replacing shellac
for this purpose in the late 1940s.
In the 1950s with improvements to polymer
production and stabilisation unplasticised (rigid)
PVC was developed in grades which could be
readily extruded or moulded.
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