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FROM EARLY DAYS UNTIL VULCANIZATION
Like most histories, this Internet history can only highlight
some key innovations and events and mention a few key names.
As it is a hypertext document it is becoming possible to
build in a number of digressions to cover key issues in
greater depth. It is a history of natural rubber and synthetic
rubber is perceived only from this aspect, that is mainly
as a threat, although some features (such as enhanced vastly
improved heat and oil resistance) have enabled some of the
attributes of natural rubber to be used to the advantage
of innovation in general. To assist with downloading times
the history has been divided into periods and this tends
to divide certain aspects of the story: thus Thomas Hancock
is mentioned on this page whereas Charles Goodyear is mentioned
on the next. The work of both men was needed to create the
right conditions for "modern rubber manufacture".
The mention of names adds another dimension. In many cases
several individuals were working on the same problem at
the same time: chance has favoured some individuals and
given them a place in history, whilst others tend to be
overlooked.
This brief history consists of this page (the Early
History) plus four further brief pages:
Stories About:
Pre-Columbian
Rubber from a variety of sources was known to the Aztecs
in Mexico, Incas in Peru, and to many tribes in the Amazon
Basin. In Mexico it was used in balls in ritualistic games
and in figurines used in worship. Some authorities also
mention waterproof clothing and footwear, but this may have
been a Spanish invention. Rubber was also burned as an unpleasant
form of incense! The typical European words for rubber,
such as caoutchouc stem from Central American Indian langauges.
The Mexican rubber did not come from Hevea brasiliensis,
but from species from Castilloa as Hevea comes from the
Amazon Basin whilst Castilloa is native to Mexico.
Columbus
Rubber was discovered by Columbus and was taken back
to the Iberian Peninsula where the resilient properties
of rubber balls were the cause of great amazement. It should
be noted that neither the rubber known to the Aztecs, nor
that found by Columbus, was based on the Hevea rubber tree,
but probably came from another species, such as Castilloa.
Indigenous technology
New World Indians had learned to extract rubber from at
least eight tropical species which yield latex. For a time
waterproof garments were manufactured from latex in America
for export back to Europe, but this practice had ceased
by the 18th century and the technology was forgotten. Most
other European languages use a derivative of the Spanish
word caucho to define rubber.
Late Renaissance science
More rubber found its way back to Europe. Early scientists
began to take an interest. Cobo was probably the first to
make observations on the coagulation of latex when it turned
from a white liquid to a dark coloured solid. Charles de
la Condamine, a French traveller, established where it grew,
François Fresneau described the sereingue or cauchuc
tree (Hevea). He noted that in order to draw the milky sap
one makes incisions with a bill-hook which must penetrate
the bark. To use the milky sap one uses a mould made of
clay according to the design one wishes to make.
Then the whole mould is exposed to thick smoke, once the
material ceases to be sticky one adds a second layer and
then others in the same way until the desired thickness
has been achieved. Fresneau used this technique to make
tarpaulins, sleeves for pumps, divers' suits, water bottles,
etc. Fresneau noted that these rubber articles tended to
stick to each other. In 1763 Fresneau discovered that rubber
would dissolve in turpentine. Priestley in England examined
its unusual properties: the latter was responsible for the
name English rubber as it could be used to erase writing.
Early nineteenth century science
Micheal Faraday established the hydrocarbon nature (C10H16)
of rubber in 1826. Before then (in 1803) Gough had discovered
that rubber warms if stretched.
Early industrialists
Rubber was exported from the Americas (mainly Brazil) to
Europe in the form of coagulated lumps (known as "bottles")
and exploitation was limited as there was a lack of ways
of working the rubber other than by cutting it into strips
- for use as elastic braces, suspenders, etc. Fresneau had
used turpentine as a solvent for rubber, but it was a pro-oxidant.
Giovanni Fabronni, an Italian whilst working in London in
1779 discovered that petroleum or naphtha was an effective
solvent and used the rubber solution to rubberize textiles.
At about the same time a hydrogen balloon employed rubberized
fabric, but the solvent may have been turpentine.
Solvents/Macintosh
Although the above suggests that a solvent had been found,
petroleum was expensive at that time and there was still
a quest to find a suitable industrial-scale solvent. This
was found in 1818 by James Syme - a medical student at Edinburgh
University - and was developed by Charles Macintosh, an
industrialist in Glasgow, who worked in association with
Professor Thomas Thomson of Glasgow University.
Macintosh was seeking an outlet for the waste products
from the new coal gas industry: coal tar naphtha formed
an excellent solvent. Macintosh contributed the two-ply
principle to waterproofing (the rubber as a sandwich filling
between two textile layers). This was especially beneficial
before vulcanization as the textile protected the rubber.
Waterproof textiles could now be produced on a large scale
initially in Glasgow and later in Manchester and the eponymous
raincoat was invented.
Mastication
It was difficult to dissolve the rubber in solvents and
in 1820 Thomas Hancock invented a device which was capable
of softening the rubber by shearing it between two rotors.
This device, known as a pickle, not only assisted in the
manufacture of macintoshes, but also enabled rubber to be
formed by moulding it. Hancock's invention opened up many
new outlets for rubber.
Calendering and extrusion
E.M. Chaffee of the Roxburg Rubber Company in the United
States patented the calender in 1836. This enabled sheets
of uniform thickness to be produced and also assisted in
frictioning rubber to fabrics. H. Bewley patented an extruder
for gutta percha in 1845, and this was soon adopted by the
rubber industry. Thus the industry was suitably equipped
with processing machinery.
Early rubber products
Hancock's Narrative includes a remarkably large number
of objects which were capable of being manufactured prior
ro the invention of vulcanization. It is interesting that
thre origins of the Michelin Company date from this period.
Barbier et Daubrée was established in 1832 at the
suggestion of Mme Daubrée (née Barker) who
was Macintosh's neice. The factory in Clermont Ferrand became
the property of Barbier's gransons, E. and A. Michelin.
Production from wild trees
Natural rubber was produced mainly within the Amazon Basin
by fairly primitive methods, but these were capable of keeping
pace with the limited demand. Shortage of labour was a chronic
problem with wild rubber and the gathering of rubber was
fraught with problems. The trees were thinly scattered in
the jungle, a few to each hectare, so that the collectors
had to make long journeys: those that were not massacred
were liable to succumb to disease in the difficult conditions.
The method of extraction of the latex, by cutting or slashing
the trees, was inefficient and harmful, and the manner of
processing the crop, by smoke coagulation, left much to
be desired, although smoking remains one of the methods
still employed to protect raw rubber. Nevertheless, some
forms of rubber (especially Fine Hard Para) were of good
quality and long after the development of plantation rubber
there were those who claimed that this was inferior to Para
rubber. Unhappily, the Amazon Valley was invaded by unscrupulous
traders who reduced the rubber-gathering native peoples
to slave conditions.
Early plantations
In 1830 a plantation of Castlloa was established in Cuba with seeds
obtained from Guatemala.
>Part 2
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