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Rubber is the name of a material which can stretch and shrink. It is a polymer. It can be either produced from natural sources (eg. natural rubber) or can be synthesised on a industrial scale. Lots of things are made from rubber, like gloves, tires, plugs, and masks and a few things can be made only from rubber.
Hevea brasiliensis is the tree that most rubber comes from. Other plants that have the special sap (called latex) are figs (Ficus elastica), Castilla (Panama rubber tree), euphorbias, lettuce, the common dandelion, Taraxacum kok-saghyz (Russian dandelion), Scorzonera tau-saghyz, and Guayule.
In the 1800s, most sap to make rubber came from South America. In 1876 Henry Wickham got seeds from rubber trees in Brazil, and took them to Kew Gardens, England, and sent them to Ceylon (Sri Lanka), Indonesia, Singapore and British Malaya. Later, Malaya (now Malaysia) made the most rubber. People tried to grow rubber in India, in 1873 at the Botanical Gardens, Kolkata. The first Hevea farms in India were made at Thattekadu in Kerala in 1902. The Congo Free State in Africa also grew a lot trees for rubber at the start of the 20th century, and most of the people who worked on those farms were forced labor. Liberia and Nigeria also started growing trees to make rubber.
Charles Marie de La Condamine presented samples of rubber to the Académie Royale des Sciences of France in 1736. In 1751 François Fresneau read a paper to the Académie (eventually published in 1755) which described many of the properties of rubber. This has been referred to as the first scientific paper on rubber.
Natural rubber melts in heat and freeze in the cold. In 1844 Charles Goodyear found a way to improve natural rubber, in a chemical process known as vulcanization, which made it useful in many more products including, decades later, tires.
In the 20th century synthetic rubbers such as Neoprene became commonplace, partly because of the scarcity of natural rubber, and partly because they can do some things that natural rubber cannot.