When you think of all the different applications of rubber, a lot of things come to mind; tires, balloons, hoses and gloves to name a few. But the first use was 3,500 years ago by the Mesoamerican Olmecs (Rubber People in Aztec) and it was a rubber ball produced for a game. They were even using an early form of vulcanization to make them.
Rubber comes from a wide variety of plants (the Olmecs were using the Castilla Elastica Tree) but the Para Tree (Hevea Brasiliensis) of the Amazon basin is considered the best (it’s the easiest to cultivate) and produces most of the Natural Rubber in use today. And like many of the things from nature that we use (rubber trees have been around at least 3 million years) it took us awhile to discover it.
Rubber is harvested by hand during the night or early morning. There are three layers to the rubber tree, the bark the cambium and the wood. First you make an incision (delicately and on alternate days) in the bark, making sure not to touch the cambium. This is done in order to preserve the tree, the bark is being tapped in order to let the latex drip out and if done correctly the tree will produce latex for up to five years. Then you switch to the other side of the tree and let the first side heal.
In the 18th century when Rubber was first introduced to Europeans its’ unique properties (elasticity, tensile strength, adhesiveness, water resistance) were noted and they began finding uses for it. The Englishman Joseph Priestly observed that it was very good at rubbing out pencil smudges on paper, and the name rubber stuck. And when the American Charles Goodyear invented Vulcanization (which made rubber much stronger) the English started thinking about how to cultivate it.
Rubber grows in areas that are warm and have plentiful rainfall and the English had abundant provinces in their Empire where they knew it would do well. There was only one problem; seeds weren’t allowed to leave Brazil under penalty of death; so that the Brazilians could maintain their monopoly. However you don’t build an Empire by following the rules or being polite. So in short order the seeds were smuggled, sprouted and shipped off to India, Sri Lanka, Singapore and Malaysia. Where the English plantations were swiftly, able to supplant the Brazilians as the top producers of rubber in the world.
Everything amped up even further with the advent of the automobile, and its’ voracious appetite for rubber. Tires (the first ones were solid rubber) hoses and belts are but a few of the myriad applications. Rubber’s water repellant nature made it perfect for covering the growing miles of electric wires and of course rain gear. In England rubbers are what they call erasers and rain shoes. A vastly different usage of the word than here in America.
In the 1930’s the Japanese (taking a page from the British Empire) began expanding their holdings throughout Asia and the Pacific Ocean. Well aware that 90% of all rubber originated in this area, many countries began looking for a synthetic form. With Pearl Harbor the Japanese swept through the region (oops there goes another rubber tree plantation, oops...) preventing the West from acquiring natural rubber.
Luckily a synthetic had been discovered (ironically by the Germans) derived from oil. The U. S. was able to keep up with the war effort (a Sherman Tank needed a half ton of rubber) because we had oil. Whereas the Nazis had trouble (they even tried using latex from dandelions) because they lacked oil as well as rubber. We won the war and synthetic rubber overtook natural rubber as the preferred kind in use. Today it makes up about 70% of the rubber in production. But as the price of oil rises (not to mention ecological concerns) natural rubber may be poised for a comeback.