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| Platics and Resin Timeline
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| It is helpful when dating or refinishing a
radio to know what materials have been used, this list helps
explain when various materials first came into common use.
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| Whilst plastics are thought of as
"new" materials there is nothing further from the
truth. Polymers have a long and full history and the following
is simply a snapshot of some of the important events.
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c.1650 John Tradescant introduces gutta
percha to the West after his travels in the East
collecting plants. Gutta percha was used to make
products from garden hoses to furniture for many years after
the
introduction to the West and was only replaced for undersea
cable insulation in the 1940's. |
| c.1839 Charles Goodyear (USA) discovers
the process of mixing natural rubber with sulphur to
make a stronger and more resilient product, the process
was later termed "vulcanisation". (see 1851 Ebonite) |
c.1851 Ebonite is patented and
commercialised by Nelson Goodyear (USA). Charles
Goodyear and Thomas Hancock both find that excess sulphur
during vulcanisation leads to ebonite. Ebonite is a
hard, dark and shiny material used for jewellery,
fountain pens, pipe stems and is the basis for most
dental plates (with pink colouring) for nearly 100 years. The
material can also be inlaid with metals or painted to produce
very decorative objects.
Ebonite is a milestone because it is the first thermosetting
material and because it involves modification of the
natural material. |
| c.1854 Shellac (mixed with woodflour)
patented as a moulding material by Samuel Peck (USA) for
use in frames and carrying cases. |
| c.1870 Hyatt brothers patent the use of
cellulose nitrate and camphor to form a horn-like
material (Celluloid). |
| c.1880 Shellac used by the Berliner
label to produce phonograph records because of the
ability to reproduce fine detail - shellac was used until
1952 when PVC was first introduced for this purpose. |
| c. 1894 Cross and Bevan introduce
cellulose acetate after research into cellulose esters
to avoid flammability concerns with celluloid |
| c.1897Adolph Spitteler (Barvaria)
discovers and patents casein plastics (probably by
accident). Casein is made from skimmed milk curdled with rennet
which is cured by immersion in formaldehyde and becomes
available as "Galalith". |
| c.1899 Arthur Smith (Britain) patents
phenol-formaldehyde resins to replace ebonite as
electrical insulation. |
| c.1907 Leo Baekeland (USA) mixes phenol
and formaldehyde to produce phenol formaldehyde resins
and obtains the first of 117 patents on
phenol-formaldehyde resin systems. |
c.1909 Leo Baekeland (USA) patents
Bakelite, the first widely used thermoset to replace
traditional materials such as wood, ivory and ebonite.
The trade name "Bakelite" will later become
synonymous with the
materials. |
| c.1924 Edmund Rossiter (Britain)
develops urea thiourea formaldehyde for the British
Cyanides Co. to give the first water-white transparent
thermosetting moulding powder. Marketed from 1926 onwards as
"Beetle". |
| c.1931 Imperial Chemical Industries -
ICI (Britain) develops polyethylene almost by accident
when E.W.Fawcett and R.O.Gibson notice a small amount of
a waxy solid produced during experiments with ethylene. This
was later isolated to produce polyethylene which had
excellent chemical resistance and insulation properties. |
| c.1933 ICI workers (R.Hill and J.W.C.
Crawford) start to develop poly(methyl methacrylate) or
PMMA - later to be commercialised under the names
"Perspex", "Lucite", "Plexiglas"
and many others. |
| c.1933 First injection moulded
polystyrene articles produced. |
