Rubber is an elastic hydrocarbon polymer which occurs as a milky emulsion (known as latex) in the sap of a number of plants but can also be produced synthetically. The major commercial source of the latex used to create rubber is the Para rubber tree, Hevea brasiliensis (Euphorbiaceae). This is largely because it responds to wounding by producing more latex. Other plants containing latex include figs (Ficus elastica), euphorbias, and the common dandelion. These have not been a major source of rubber, though when Germany was cut off from supplies of rubber during World War II, attempts were made to use such sources, before being supplanted by the development of synthetic rubber. In chemistry, a hydrocarbon is any chemical compounds that consists only of carbon (C) and hydrogen (H). ... A polymer is a generic term used to describe a substantially long molecule. ... Emulsion An emulsion is a mixture of two immiscible substances. ... The LaTeX logo, typeset with LaTeX LATEX is a document preparation system for the TeX typesetting program. ... Binomial name Hevea brasiliensis {{{author}}} Latex being collected from a wounded rubber tree The Pará rubber tree (Hevea brasiliensis), often simply called rubber tree, is a tree belonging to the family Euphorbiaceae. ... Genera See text Ref: Euphorbiaceae in The Families of Flowering Plants, as of 2002-07-13 The Spurge family (Euphorbiaceae) is a large family of flowering plants with 280 genera and around 6000 species. ... Species About 800, including: Ficus altissima Ficus americana Ficus aurea Ficus benghalensis - Indian Banyan Ficus benjamina - Weeping Fig Ficus broadwayi Ficus carica - Common Fig Ficus citrifolia Ficus drupacea Ficus elastica Ficus godeffroyi Ficus grenadensis Ficus hartii Ficus lyrata Ficus macbrideii Ficus macrophylla - Moreton Bay Fig Ficus microcarpa - Chinese Banyan Ficus... Ficus elastica, also called rubber tree, rubber plant, Indian rubber tree, is a species of plant of the fig genus. ... This article needs cleanup. ... Species Taraxacum officinale Taraxacum japonicum Taraxacum albidum and a few others. ... Mushroom cloud from the nuclear explosion over Nagasaki rising 18 km (over 11 miles) into the air. ... Synthetic rubber is a type of artificially-made polymer material which acts as an elastomer. ...

In places like Kerala, where coconuts are in abundance, the shell of half a coconut is used as the collection container for the latex. The shells are attached to the tree via a short sharp stick and the latex drips down into it overnight. This usually produces latex up to a level of half to three quarters of the shell. The latex from multiple trees are then poured into flat pans and this is mixed with formic acid, which serves as a coagulant. After a few hours, the very wet sheets of rubber are wrung out by putting them through a press before they are sent onto factories where vulcanization and further processing is done. Kerala (കേരളം - Keralam) is a state in South India, occupying a narrow strip of Indias southwestern coast. ... Formic acid (systematically called methanoic acid) is the simplest carboxylic acid. ...

Aside from a few natural product impurities, natural rubber is essentially a polymer of isoprene units, a hydrocarbon diene monomer. Syntheic rubber can be made as a polymer of isoprene or various other monomers. Rubber is believed to have been named by Joseph Priestley, who discovered in 1770 that dried latex rubbed out pencil marks. The material properties of rubber make it an elastomer. Isoprene Chemical name 2-Methyl-1,3-butadiene Chemical formula C5H8 Molecular mass 68. ... Dienes are hydrocarbons which contain two double bonds. ... In chemistry, a monomer (from Greek mono one and meros part) is a small molecule that may become chemically bonded to other monomers to form a polymer. ... Joseph Priestley (March 13, 1733 - February 6, 1804) was an English chemist, dissenting clergyman, and educator. ... 1770 was a common year starting on Monday (see link for calendar). ... The term elastomer is often used interchangeably with the term rubber, and is preferred when referring to vulcanisates. ...

History

In its native Central America and South America, rubber has been collected for a long time. The Mesoamerican civilizations used rubber mostly from Castilla elastica. The Ancient Mesoamericans had a ball game using rubber balls (see: Mesoamerican ballgame), and a few Pre-Columbian rubber balls have been found (always in sites that were flooded under fresh water), the earliest dating to about 1600 BC. According to Bernal Díaz del Castillo, the Spanish Conquistadores were so astounded by the vigorous bouncing of the rubber balls of the Aztecs that they wondered if the balls were enchanted by evil spirits. The Maya also made a type of temporary rubber shoe by dipping their feet into a latex mixture. Rubber was used in various other contexts, such as strips to hold stone and metal tools to wooden handles, and padding for the tool handles. While the ancient Mesoamericans did not have vulcanization, they developed organic methods of processing the rubber with similar results, mixing the raw latex with various saps and juices of other vines, particularly Ipomoea alba, a species of Morning glory. Central America is the region of North America located between the southern border of Mexico and the northwest border of Colombia, in South America. ... South America South America is a continent crossed by the equator, with most of its area in the Southern Hemisphere. ... Mesoamerica is the region extending from central Mexico south to the northwestern border of Costa Rica that gave rise to a group of stratified, culturally related agrarian civilizations spanning an approximately 3,000-year period before the European discovery of the New World by Columbus. ... Great Ball Court at Chichén Itzá A Ball Court Goal, Chichén Itzá Ball court marker, from the Maya site of Chinkultic. ... The term Pre-Columbian is used to refer to the cultures of the New World in the era before significant European influence. ... (Redirected from 1600 BC) Centuries: 18th century BC - 17th century BC - 16th century BC Decades: 1650s BC 1640s BC 1630s BC 1620s BC 1610s BC - 1600s BC - 1590s BC 1580s BC 1570s BC 1560s BC 1550s BC Events and trends Egypt: End of Fourteenth Dynasty The creation of one of... Bernal Díaz del Castillo (1492 or 1493 - 1581) was a conquistador, who wrote an eyewitness account of the conquest of Mexico under Hernán Cortés. ... Conquistador (meaning Conqueror in the Spanish language) is the term used to refer to the soldiers, explorers, and adventurers who brought much of the Americas and Asia Pacific under Spanish rule between the 15th and 17th centuries. ... The Aztecs were a Mesoamerican people of central Mexico in the 14th, 15th and 16th century. ... The Maya are people of southern Mexico and northern Central America (Guatemala, Belize, western Honduras, and El Salvador) with some 3,000 years of history. ... Moonflower is a climbing vine, related to the morning glory. ... Categories: Stub | Flowers ...

In Brazil the natives understood the use of rubber to make water-resistant cloth. A story says that the first European to return to Portugal from Brazil with samples of such water-repellent rubberized cloth so shocked people that he was brought to court on the charge of witchcraft.

When samples of rubber first arrived in England, it was observed that a piece of the material was extremely good for rubbing out pencil marks on paper. This was the origin of the material's English name of 'rubber'. Blocks of the material are still used for this purpose, and known as 'rubbers' in British English, causing occasional amusement to speakers of American English, to whom a 'rubber' is a condom (usually made from latex). (American English uses 'eraser' to refer to the rubber block.) Royal motto: Dieu et mon droit (French: God and my right) Englands location within the UK Official language English de facto Capital London de facto Largest city London Area  - Total Ranked 1st UK 130,395 km² Population  - Total (2001)  - Density Ranked 1st UK 49,138,831 377/km² Religion... A couple of very simple pencils Colored pencils are usually used for drawing instead of writing. ... British English is a term primarily used by people outside of the UK to refer to the form of the English language spoken in the British Isles. ... American English or U.S. English is the diverse form of the English language used mostly in the United States of America. ... A condom is a device, usually made of latex, that covers a mans penis during sexual intercourse to avoid pregnancy and/or sexually transmitted diseases (STD) such as gonorrhea, syphilis and HIV. They are also known as prophylactics, as well as a number of colloquial or slang terms, such... The LaTeX logo, typeset with LaTeX LATEX is a document preparation system for the TeX typesetting program. ...

The para rubber tree initially grew in South America, where it was the main source of what limited amount of latex rubber was consumed during much of the 19th century. About 100 years ago, the Congo Free State in Africa was a significant source of natural rubber latex, but after repeated efforts (see Henry Wickham) it was successfully cultivated in Southeast Asia, where it is now widely grown. South America South America is a continent crossed by the equator, with most of its area in the Southern Hemisphere. ... Alternative meaning: Nineteenth Century (periodical) (18th century — 19th century — 20th century — more centuries) As a means of recording the passage of time, the 19th century was that century which lasted from 1801-1900 in the sense of the Gregorian calendar. ... The Congo Free State was a kingdom privately and controversially owned by King Leopold II of Belgium that included the entire area now known as the Democratic Republic of the Congo. ... Henry Wickham was responsible for gathering 70,000 seeds from the rubber-bearing tree, Hevea brasiliensis, in the Manaus area of Brazil in 1876. ... Location of Southeast Asia Southeast Asia is a subregion of Asia. ...

Current sources of rubber

Today Asia is the main source of natural rubber. Over half of the rubber used today is synthetic, but several million tonnes of natural rubber are still produced annually, and is still essential for some industries, including automotive and military. A satellite composite image of Asia Asia is the central and eastern part of the continent of Eurasia, defined by subtracting the European peninsula from Eurasia. ... In chemistry, the phrase chemical synthesis appears to have one of two meanings. ...

Hypoallergenic rubber can be made from Guayule. See basic definition at Wiktionary. ... Guayule plants Guayule (Parthenium argentatum, pronounced wa-YOO-lee) is a shrub in the Parthenium genus of the Asteraceae family that is mostly distributed in the southwestern United States and northern Mexico. ...

Early experiments in the development of synthetic rubber led to the invention of Silly Putty. Synthetic rubber is a type of artificially-made polymer material which acts as an elastomer. ... Silly Putty is a silicone plastic clay, marketed as a toy for children by Binney & Smith Inc. ...

Natural rubber is often vulcanized, a process by which the rubber is heated and sulfur is added to improve resilience and elasticity. The process of vulcanization greatly improved the durability and utility of rubber from the 1830s on. The successful development of vulcanisation is most closely associated with Charles Goodyear. Carbon black is often used as an additive to rubber to improve its strength, especially in vehicle tires. Vulcanization is the process of cross-linking elastomer molecules to make the bulk material harder, less soluble and more durable. ... General Name, Symbol, Number sulfur, S, 16 Chemical series nonmetals Group, Period, Block 16 (VIA), 3, p Density, Hardness 1960 kg/m3, 2 Appearance Lemon yellow at STP Atomic properties Atomic weight 32. ... Events and Trends Dutch-speaking farmers known as Voortrekkers emigrate northwards from the Cape Colony. ... Charles Goodyear, as illustrated in an 1891 Scientific American article Charles Goodyear (December 29, 1800 - July 1, 1860) is popularly renown as the inventor of vulcanized rubber. ... Soot, also called lampblack or carbon black, is a dark powdery deposit of unburned fuel residues, usually composed mainly of amorphous carbon, that accumulates in chimneys, automobile mufflers and other surfaces exposed to smoke—especially from the combustion of carbon-rich organic fuels in the lack of sufficient oxygen. ...

Rubber as a clothing material is fetishized by some people, perhaps on the basis that the garment forms a "second skin" that acts as a surrogate for the wearer's own skin. This is known as rubber fetishism. A fetish (from French fétiche, from Portuguese feitiço, from Latin facticius) is a natural object believed to have supernatural powers, or in particular a thing created by people that has power over people. ... Rubber fetishism is the fetishistic attraction to people wearing rubber, or in certain cases, to the garments themselves. ...

See also

• elastic
• tire

There are separate articles about elasticity in economics, and about British rubber bands. ... Firestone tire A tire (US spelling) or tyre (UK spelling) is a roughly toroidal piece of (usually) rubber placed on a wheel to cushion it. ...

External link

International Rubber Research & Development Board (http://www.irrdb.com/IRRDB/NaturalRubber/Default.htm)