Most of us use something made out of rubber every day. In fact, it’s hard for us to get far without it—the tyres on our cars, buses and bicycles are all made from rubber.
About half of the world’s rubber ends up as tyres, but there are many other uses for this versatile material.
The properties of rubber enable it to be soft and flexible when used to make birthday balloons, protective gloves and PVA glue, or it can be made strong and resilient enough for use in small inflatable boats or roofing material.
Rubber is used widely in sports and outdoor clothing items such as wellington boots, wetsuits and swimming hats, and is sometimes even used as part of artificial hearts.
What Is Rubber?
Rubber is an elastomer type polymer (a large, chain-like molecule made up of many smaller molecules) which has the ability to return to its original shape after being stretched.
There are lots of different kinds of rubber, but rubber mainly falls into two types: natural or synthetic.
Natural rubber occurs as latex (a milky liquid) in the sap of some plants. The Pará rubber tree (Hevea Brasilien) is the main commercial source of natural rubber and was originally found in Brazil.
This plant has also been introduced to several countries in the Far East such as Malaysia, Indonesia, Burma, Cambodia, China and Vietnam.
Synthetic rubbers are created artificially in chemical plants using petrochemicals, a process which can produce a vast amount of waste.
Although more than half of the rubber we now use is synthetic, natural rubber is still essential in many industries, with several million tons of natural rubber still produced every year.
History of Rubber
Rubber is native to Central and South America, and was first used by ancient Mesoamerican civilizations as part of tools, and to make small balls for games.
Christopher Columbus was the first European to take rubber balls back to Europe in the 1490’s, but at this stage the beneficial properties of rubber were not fully recognised.
In 1840, Charles Goodyear invented a chemical process called vulcanization, used to strengthen rubber. During vulcanization, natural rubber is heated to about 140°C before sulphur, peroxide or bisphenol are added.
This discovery revolutionised the use and applications of rubber and led to an increased demand.
As cars and bicycles became more popular, demand increased even further. Unfortunately, the large-scale production of natural rubber had tragic consequences for the indigenous population of the Congo and Amazon, and “at least 30,000 people were killed in the race to source rubber” (source).
During the World Wars, demand for rubber increased again, but natural rubber became increasingly difficult to get hold of, leading to the production of the first synthetic rubber.
The Production of Natural Rubber
Natural rubber is harvested from trees by a method called tapping. An incision is made in the tree so that the milky latex can be extracted (the incision will later heal naturally).
The latex is then taken to a processing plant where it is diluted with water, treated with acid then rolled and dried.
Is Natural Rubber Eco-Friendly?
The good news about natural rubber is that it is biodegradable. Many household natural rubber products, such as latex gloves, can be disposed of in landfill without any environmental damage.
Natural rubber is also a renewable resource. After 12 years, a rubber tree will no longer be able to produce latex, but at that point it can be replaced by a new sapling.
The whole process of growing and harvesting natural rubber has minimal impact on the environment, making it a much better choice than synthetic rubber or other materials such as plastic.
If managed responsibly, rubber trees can actually help the environment by reducing carbon dioxide emissions from deforestation.
Rubber can also be recycled into lots of useful items, rather than just ending up in landfill. For example, old car tyres can be recycled and used to create safe surfaces in playgrounds.
However, there is a negative side to the rubber industry.
Vast areas of natural forests have been cleared to grow rubber plantations to meet increasing global demand, and rapid changes to use of land on such a wide scale can be catastrophic to the local wildlife and environment.
The rubber industry has not yet had the same level of negative publicity as palm oil (which is leading to more control and legislation), and issues such as human rights violations, corruption and deforestation are big problems within the rubber industry.
Natural rubber is biodegradable and eco-friendly, but you might prefer to check if natural rubber products are from a well-managed and sustainable source before you buy them.