Rubber, the most fascinating natural material, is also known by the Maya name caoutchouc. Knowledge of the elastic properties of rubber was brought to Europe by Christopher Columbus, who observed inhabitants of Haiti playing with bouncing balls. Considerably later, in 1615, a Spanish explorer reported how milk (latex) gathered from incisions made on specific tropical trees was brushed on cloaks, rendering them waterproof after drying, or on earthen, bottle shaped moulds to produce containers. It was not until 1735 that the French geographical expedition identified caoutchouc sap of the hevea brasiliensis tree, today called the rubber tree, because rubber has the capability to erase pencil marks. Hevea trees only grow ten degrees north or south or the equator, and need heavy annual rainfalls of about 250 cm and tropical climate. The rubber tree is presently cultivated in Malaysia, Ceylon, south-east Asia and West Africa. Wild rubber is still harvested in Brazil and Peru.
Latex is only workable when freshly tapped from the rubber tree, thus Europeans struggled considerably to find solvents for caoutchouc to make it spreadable after it arrived in Europe in its dried state. Efforts utilizing ether, turpentine or naphtha (a waste from coal-gas plants) were only partially successful since the water proof items, produced from rubber remained sticky particularly when warm, and turned to dust in the hot summers. Moreover, these rubber items were odorous, perishable and became brittle and even cracked upon the use during extreme cold winters.
Nevertheless, a large number of products were manufactured in the early 1800s such as air mattresses, portable bathtubs, waterproof mail bags and boots. In the 1820as a machine was built to rapidly cut rubber into small pieces which generated heat and thus facilitating the fusing of rubber scraps into blocks.
Riding on the rubber boom of the 1830s, Charles Goodyear after considerable experimentation discovered the curing process during heating. The new substance did not melt. It was durable and retained pliability and elasticity when cold. This technique of vulcanization is still used today.
In 1860 John B Dunlop patented and developed a pneumatic rubber tire based on Goodyear’s invention, which eventually made the bicycle popular and had an impact on the auto industry several decades later.