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1844, 8 weeks before Hancock’s application. Though in ill health and poverty, Goodyear battled to
see that his contributions were recognized. Others entered the fight with related claims but history

recognizes Goodyear for his scientific insight and Hancock for his applications of NR producing a

number of products. (Chapter 1 contains more about the ventures of Charles Goodyear.)
Goodyear had trouble defending his patent, piling up huge debts before he died in 1860. Daniel
Webster defended him in one of his patent infringement cases. By 1858, the yearly value of rubber
goods produced in the United States was about $5 million. The major rubber producing plants clus-
tered about Akron, Ohio, which the Goodyear Company founded in 1870.
Vulcanized rubber had many applications but one of the greatest is probably the “rubber tire.”
Early tires were made of solid NR and gave a stiff ride. John B. Dunlap rediscovered the air-

filled tire, pneumatic tire, in 1887. At this time, the automobile was just beginning its ownership of
the roads. Bicycles made by various small shops, including those made by the Wright Brothers of
Dayton, Ohio, were being viewed as a poor man’s horse. It did not need food nor did you need to
tend to it or to its droppings. As roads, even gravel and dirt roads, become more common place in
the cities, bicycles began to be the vehicle of choice here in America and in Europe. The air-fi lled
tire gave a softer ride and became the tire of choice for cyclists. It also increased the value and
need for NR. As cars and then trucks entered as major conveyers of people and goods, the need for
greater amounts of rubber increased.
During this time, seeds from the Amazon valley were planted in British colonies in the east
where plantations were founded using native labor, often enslaved, to harvest the NR. Of the vari-
ous NR-producing trees, Hevea Brasiliensis was the best. With World War I, the need for rubber by
the British and American forces was critical. To cope with this need several avenues were explored.
Alternative rubber producing plants were explored emphasizing plants that would be producing
within a year or less and which could survive under milder climates, milder with respect to temper-
ature and need for water. While the exploration of such plants continues today, this avenue was not
successful in supplying the greatly increased rubber needs (Figure 9.4).
The second avenue involved developing a synthetic rubber (SR). English scientist Michael

Faraday helped set the stage by analyzing NR finding that it was generally composed of repeat
units originally described by Faraday as C H , which was latter rendered (C H ) . NR was later
10 16 5 8 n
separated into three parts, an oil, tar, and “spirit.” The most volatile “spirit” portion was evalu-
ated and found to contain largely the isoprene unit. The task then was to produce isoprene syn-
thetically, and then to convert it to rubber. By 1900, the synthesis of isoprene had been achieved,
though not easily. Often, isoprene samples spontaneously underwent addition forming a material
similar to NR.

Bark

Tapping panel Latex

Cup for latex

FIGURE 9.4 Harvesting of rubber latex from a rubber tree.

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