He put his family in debt to finance experiments to make the material suitable for industrial use. In short, he went anywhere he could find investors and places to conduct his experiments. He inhaled the fumes of toxic concoctions, including nitric acid, lime, and turpentine, that he mixed together and kneaded into the rubber to make it stable. There was no stopping Goodyear.
Goodyear thought he had found the answer when he discovered that nitric acid smoothed out rubber and made it less sticky. He won a contract from the United States Post Office in Boston to make rubber mailbags, but they, too, melted in hot weather.
According to biographers, while working at the Eagle India Rubber Company, Goodyear accidentally combined rubber and sulfur upon a hot stove.
And, when he raised the heat, it actually hardened. It would take Goodyear several more years to recreate the chemical formula and perfect the process of mixing sulfur and rubber at a high temperature; he patented the process in , the year after establishing the Naugatuck India-Rubber Company in Naugatuck.
Goodyear named his discovery vulcanization, after Vulcan, the Roman god of fire. He licensed his patent to manufacturers and showcased it at exhibitions. The vulcanization process put Naugatuck, Connecticut, on the map as a leading site of rubber manufacturing during the 19th and 20th centuries. Numerous rubber companies operated in the town under the Goodyear license, including Uniroyal, which made the popular Keds sneakers.
Eventually, foreign competition would bring down the rubber industry in Naugatuck. He spent much of the fortune he earned from his patent fighting patent infringements in courts in the United States and abroad.
Thanks to its connected system, the Hevea tree bleeds latex when a special incision is made in its trunk Figure 2.
Without the latex tube connections, the Castilla tree does not bleed latex, making harvest of rubber more difficult. In , Charles Goodyear invented the vulcanization process, solving many of the problems associated with rubber. Vulcanization is the process of treating rubber with sulfur and heat, to harden it while keeping its elasticity.
It prevents rubber from melting in the summer and cracking in the winter. A few years after this important discovery, in , Dunlop invented the air-filled rubber tire, making rubber an extremely important raw material worldwide. Rubber became an essential material for the Industrial Revolution. From to , businessmen were pushing entrepreneurs and traders to increase the amount of rubber extracted from Amazonian trees.
During this period, the Brazilian Amazon was the only source of rubber and they controlled the price, making rubber expensive. At the same time, as more and more industry was developing in Europe and USA, more uses for rubber were being found [ 4 ].
Rubber was such an important material for Brazilians that they prohibited the export of rubber seeds or seedlings. However, in , H. Wickham managed to smuggle 70, rubber seeds, hidden in banana leaves, and brought them to England. From those seeds, only 1, seedlings survived and were sent to Malaysia to start the first rubber plantations in Asia.
While working there, he found the first 11 rubber trees that were planted in Malaysia and he started promoting the establishment of rubber tree plantations. Sometime later, he developed a revolutionary method for harvesting latex from the Hevea tree by continuous tapping. Tapping is the process of removing the latex from the tree. The new plantations were more competitive in price, so from the end of the nineteenth century until the First World War, rubber collection from wild sources in tropical America declined tremendously.
During the war, the supply of rubber was cut off. The USA, Germany, and Russia started searching for alternative rubber sources, either natural or synthetic, since the Amazonian trees were not supplying enough rubber for their needs [ 3 ].
Several research programs started in these countries, but, after the war, the supply of rubber from Malaysian plantations started again and the effort to look for new rubber sources almost disappeared. In recent years, the search for alternative sources of rubber has begun again. There are three main reasons for this:.
First of all, the rubber trees are exposed to several diseases and since Asian rubber plantations started from only a handful of seeds, all the trees are genetically very similar. Less genetic variation means lower ability to fight against plant diseases. If one tree becomes sick, the illness can rapidly spread to the entire plantation.
Today, the most important and dangerous disease that Hevea brasiliensis suffers from is called South American leaf blight disease. This disease can cause the devastation of an entire plantation. It is still confined to the tropical Americas, but if it arrives in Asia, it could mean the end of the rubber plantations. Under natural conditions, rubber trees commonly grow with a lot of space between them.
In nature, serious damage to Hevea from South American leaf blight is unusual, because the other kinds of trees growing in between the rubber trees are not susceptible to the disease and act as barriers.
But, on plantations where rubber trees grow very closely together, it can become lethal. Second of all, an important threat to the natural rubber market is the very competitive and fast-growing market for palm oil and its side products. There is an increasing demand for both rubber and palm oil but, in Malaysia, the area in which Hevea brasiliensis is being grown is not decreasing, however, the area dedicated to grow oil palm is increasing.
If the continuous growth of oil palm plantations does not stop, either the natural forest or the Hevea plantations will have to get smaller to make room for new crops of oil palms.
However, since it's identification around three millennia ago, rubber has been greatly developed into the modern substance familiar today. First identified and collected in Central and South American in about B. Harvested from a plant, these ancient peoples formed balls with the substance, and used these balls for primitive bouncing games. Although games were the primary use for rubber at the time, traces of the substance have also been found in the construction of metal and stone tools, used mainly to hold these materials to a wooden handle.
Over time these early humans discovered that rubber was waterproof, and could be used to create water resistant clothing. When Europeans first came in contact with rubber, they were so shocked by its properties they thought it was witchcraft.
However, by rubber had been introduced into English society by Joseph Priestley.
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