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In 1907, Leo Hendrick
Baekeland, a Belgian scientist working in New York, discovered and patented
a revolutionary new synthetic material. His invention, which he named
'Bakelite', was of enormous technological importance, and effectively
launched the modern plastics industry.
The term 'plastic' comes from
the Greek plassein, meaning 'to mould' Some plastics are derived from
natural sources, some are semi-synthetic (the result of chemical action on
a natural substance), and some are entirely synthetic, that is, chemically
engineered from the constituents of coal or oil. Some are 'thermoplastic',
which means that, like candlewax, they melt when heated and can then be
reshaped. Others are 'thermosetting': like eggs, they cannot revert to
their original viscous state, and their shape is thus fixed for ever
Bakelite had the distinction of being the first totally synthetic
thermosetting plastic.
The history of today's
plastics begins with the discovery of a series of semi-synthetic
thermoplastic materials in the mid-nineteenth century. The impetus behind
the development of these early plastics was generated by a number of
factors - immense technological progress in the domain of chemistry,
coupled with wider cultural changes, and the pragmatic need to find
acceptable substitutes for dwindling supplies of 'luxury' materials such as
tortoiseshell and ivory.
Baekeland's interest in
plastics began in 1885 when, as a young chemistry student in Belgium, he
embarked on research into phenolic resins, the group of sticky substances produced
when phenol (carbolic acid) combines with an aldehyde (a volatile fluid
similar to alcohol). He soon abandoned the subject, however, only returning
to it some years later. 8y 1905 he was a wealthy New Yorker, having
recently made his fortune with the invention of a new photographic paper.
While Baekeland had been busily amassing dollars, some advances had been
made in the development of plastics. The years 1899 and 1900 had seen the
patenting of the first semi-synthetic thermosetting material that could be
manufactured on an industrial scale. In purely scientific terms,
Baekeland's major contribution to the field is not so much the actual
discovery of the material to which he gave his name, but rather the method
by which a reaction between phenol and formaldehyde could be controlled,
thus making possible its preparation on a commercial basis. On 13 July
1907, Baekeland took out his famous patent describing this preparation, the
essential features of which are still in use today.
The original patent outlined a
three-stage process, in which phenol and formaldehyde (from wood or coal)
were initially combined under vacuum inside a large egg-shaped kettle. The
result was a resin known as Novalak, which became soluble and malleable
when heated. The resin was allowed to cool in shallow trays until it
hardened, and then broken up and ground into powder. Other substances were
then introduced: including fillers, such as woodflour, asbestos or cotton,
which increase strength and moisture resistance, catalysts (substances to
speed up the reaction between two chemicals without joining to either) and
hexa, a compound of ammonia and formaldehyde which supplied the additional
formaldehyde necessary to form a thermosetting resin. This resin was then
left to cool and harden, and ground up a second time. The resulting
granular powder was raw Bakelite, ready to be made into a vast range of
manufactured objects. In the last stage, the heated Bakelite was poured
into a hollow mould of the required shape and subjected to extreme heat and
pressure, thereby 'setting' its form for life.
The design of Bakelite
objects, everything from earrings to television sets, was governed to a
large extent by the technical requirements of the moulding process. The
object could not be designed so that it was locked into the mould and
therefore difficult to extract. A common general rule was that objects
should taper towards the deepest part of the mould, and if necessary the
product was moulded in separate pieces. Moulds had to be carefully designed
so that the molten Bakelite would flow evenly and completely into the
mould. Sharp corners proved impractical and were thus avoided, giving rise
to the smooth, 'streamlined' style popular in the 1930s. The thickness of
the walls of the mould was also crucial’ thick walls took longer to cool
and harden, a factor which had to be considered by the designer in order to
make the most efficient use of machines.
Baekeland's invention,
although treated with disdain in its early years, went on to enjoy an unparalleled
popularity which lasted throughout the first half of the twentieth century.
It became the wonder product of the new world of industrial expansion -
'the material of a thousand uses'. Being both non-porous and
heat-resistant, Bakelite kitchen goods were promoted as being germ-free and
sterilisable. Electrical manufacturers seized on its insulating properties,
and consumers everywhere relished its dazzling array of shades, delighted
that they were now, at last, no longer restricted to the wood tones and
drab browns of the preplastic era. It then fell from favour again during
the 1950s, and was despised and destroyed in vast quantities. Recently,
however, it has been experiencing something of a renaissance, with renewed
demand for original Bakelite objects in the collectors' marketplace, and
museums, societies and dedicated individuals once again appreciating the
style and originality of this innovative material.
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