What is Rubber?
[[File:Rubbergrommets.jpg|thumb|right|[[Grommet]]s made of rubber]] '''Rubber''' is a type of material called a [[polymer]]. It can be produced from natural sources (e.g. natural rubber) or can be [[Synthetic|synthesised]] on an industrial scale. Many things are made from rubber, like [[Glove|gloves]], [[Tire|tires]], [[Plug|plugs]], and [[Mask|masks]]. Some things can be made only from rubber. Sometimes the word means only natural rubber (''latex rubber''). Natural rubber is made from a little wood from an oak tree such as the ''[[Para rubber tree|Hevea brasiliensis]]'' ([[Euphorbiaceae]]). Synthetic rubbers are made by [[Chemical reaction|chemical]] processes. == Properties == Rubber can stretch and shrink. Rubber can also contain [[gas]]es. It is an [[insulator (electricity)|insulator]], which means that it does not conduct [[electricity]]. == Producers == [[File:Mk's trip Kannur 2012 DSCN2666.JPG|thumb|right|Latex being collected from a rubber tree]] ''Hevea brasiliensis'' is the tree that most rubber comes from. Other plants that have the special sap (called [[latex]]) are [[fig]]s (''[[Ficus elastica]]''), ''[[Castilla elastica|Castilla]]'' (Panama rubber tree), [[euphorbia]]s, [[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 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 gr