
:''This article is about the material rubber, for other uses see Rubber (disambiguation)'' 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 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. 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. ==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 Spain 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 civilization 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. 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.) 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. ==Current sources of rubber== Today Asia is the main source of natural rubber. Over half of the rubber used today is chemical synthesis, but several million tonnes of natural rubber are still produced annually, and is still essential for some industries, including automotive and military. Hypoallergenic rubber can be made from Guayule. Early experiments in the development of synthetic rubber led to the invention of Silly Putty. Natural rubber is often Vulcanization, 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. Rubber as a clothing material is fetishism 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. == See also == * elastic * tire == External link == [http://www.irrdb.com/IRRDB/NaturalRubber/Default.htm International Rubber Research & Development Board] Materials Organic polymers Terpenes and terpenoids
''The following was moved from the aricle page:'' User:Olivier 04:48 Nov 27, 2002 (UTC) ''Can anyone expand on this article? I wrote the very first bit, but I have no information on how synthetic rubber is produced! user:Mark Ryan I have a half-memory that the seeds were initially smuggled out of Brazil, which, if true, would be the most profitable act of industrial espionage of all time... I need to check on this -- user:Malcolm Farmer ---- I am trying to understand why half of the world's rubber is produced synthetically. Is synthetic rubber cheaper or more expensive than natural one? Is it better or worse than natural one? Is not enough natural one produced in the world? User:AxelBoldt 10:43, 5 May 2004 (UTC) ===Edit=== I moved the recent addition on Asian natural rubber to the previous paragraph, which deals with natural rubber. I removed the blight concern and link, because there is nothing remarkable that people might be concerned with a crop blight: this is true for any crop, and unless we go into it in some depth — which would be interesting — the squib of sentence was not useful. The link was to a syllabus; from long experience on my own website, syllabus pages very often disappear when the quarter or semester is over. — User:Bill Thayer 17:20, 15 Feb 2005 (UTC) == Synthetic vs Natural == Synthetic rubbers have fundamentally different properties to natural rubbers and are therefore used for different purposes. For example, nitrile rubber has decreased permeability to many solvents and increased abrasion resistance. I'd suggest the article needs an update as natural rubber and synthetic rubbers need to be more clearly delineated. Also a short monologue on chemical additives and potential allergies would be of use as they are of fundamental importance to a significant minority (natural rubber can cause a potentially fatal allergy). I will try to address this in the coming weeks. --User:JohnSpashett 09:29, 12 Jun 2005 (UTC) Where can i found Kautschuk? == Kautschuk == C an you help me? I want to know something about Kautschuk.
See other meanings of words starting from letter:
Words begining with Rubber:
Rubber
Rubber
Rubber-Band_Man_(Static_Shock)
Rubber-hose_cryptanalysis
Rubber-hose_cryptanalysis
Rubber-necking
Rubber-stamp
Rubber-stamp_legislature
Rubber-tired_metro
Rubber-tired_metro
Rubber-tired_underground
Rubber-tired_underground
Rubber-tyred_metro
Rubberbanding
Rubberbandman747
Rubberen_Robbie
Rubbergate
Rubberism
Rubberist
Rubberneck
Rubberneck
Rubbernecking
Rubbers
Rubberstamp
Rubberstamp_(politics)
Rubbery_Figures
Rubbery_figures
Rubbery_polymer
Rubber_(baseball)
Rubber_(disambiguation)
Rubber_and_PVC_fetishism
Rubber_baby_buggy_bumpers
Rubber_ball
Rubber_band
Rubber_band
Rubber_Band_Grenade
Rubber_band_ligation
Rubber_Bowl
Rubber_bridge
Rubber_bullet
Rubber_bullets
Rubber_bullet_gun
Rubber_bung
Rubber_bung
Rubber_Bungs
Rubber_cement
Rubber_City
Rubber_Duck
Rubber_duck
Rubber_Duckie
Rubber_duckie
Rubber_ducky
Rubber_fetish
Rubber_fetishism
Rubber_hose_cryptanalysis
Rubber_hound
Rubber_hound
Rubber_mallet
Rubber_mixing
Rubber_necking
Rubber_plant
Rubber_Soul
Rubber_Soul
Rubber_soul
Rubber_stamp
Rubber_stamps
Rubber_stamp_(politics)
Rubber_stamp_legislature
Rubber_tired_metro
Rubber_tired_metro
Rubber_tree
Rubber_Vine
Rubber
:''This article is about the material rubber, for other uses see Rubber (disambiguation)'' 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 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. 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. ==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 Spain 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 civilization 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. 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.) 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. ==Current sources of rubber== Today Asia is the main source of natural rubber. Over half of the rubber used today is chemical synthesis, but several million tonnes of natural rubber are still produced annually, and is still essential for some industries, including automotive and military. Hypoallergenic rubber can be made from Guayule. Early experiments in the development of synthetic rubber led to the invention of Silly Putty. Natural rubber is often Vulcanization, 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. Rubber as a clothing material is fetishism 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. == See also == * elastic * tire == External link == [http://www.irrdb.com/IRRDB/NaturalRubber/Default.htm International Rubber Research & Development Board] Materials Organic polymers Terpenes and terpenoids
Rubber
''The following was moved from the aricle page:'' User:Olivier 04:48 Nov 27, 2002 (UTC) ''Can anyone expand on this article? I wrote the very first bit, but I have no information on how synthetic rubber is produced! user:Mark Ryan I have a half-memory that the seeds were initially smuggled out of Brazil, which, if true, would be the most profitable act of industrial espionage of all time... I need to check on this -- user:Malcolm Farmer ---- I am trying to understand why half of the world's rubber is produced synthetically. Is synthetic rubber cheaper or more expensive than natural one? Is it better or worse than natural one? Is not enough natural one produced in the world? User:AxelBoldt 10:43, 5 May 2004 (UTC) ===Edit=== I moved the recent addition on Asian natural rubber to the previous paragraph, which deals with natural rubber. I removed the blight concern and link, because there is nothing remarkable that people might be concerned with a crop blight: this is true for any crop, and unless we go into it in some depth — which would be interesting — the squib of sentence was not useful. The link was to a syllabus; from long experience on my own website, syllabus pages very often disappear when the quarter or semester is over. — User:Bill Thayer 17:20, 15 Feb 2005 (UTC) == Synthetic vs Natural == Synthetic rubbers have fundamentally different properties to natural rubbers and are therefore used for different purposes. For example, nitrile rubber has decreased permeability to many solvents and increased abrasion resistance. I'd suggest the article needs an update as natural rubber and synthetic rubbers need to be more clearly delineated. Also a short monologue on chemical additives and potential allergies would be of use as they are of fundamental importance to a significant minority (natural rubber can cause a potentially fatal allergy). I will try to address this in the coming weeks. --User:JohnSpashett 09:29, 12 Jun 2005 (UTC) Where can i found Kautschuk? == Kautschuk == C an you help me? I want to know something about Kautschuk.
See other meanings of words starting from letter:
R
RA | RB | RC | RD | RE | RF | RG | RH | RI | RJ | RK | RL | RM | RN | RO | RP | RS | RT | RU | RW | RX | RY | RZ |Words begining with Rubber:
Rubber
Rubber
Rubber-Band_Man_(Static_Shock)
Rubber-hose_cryptanalysis
Rubber-hose_cryptanalysis
Rubber-necking
Rubber-stamp
Rubber-stamp_legislature
Rubber-tired_metro
Rubber-tired_metro
Rubber-tired_underground
Rubber-tired_underground
Rubber-tyred_metro
Rubberbanding
Rubberbandman747
Rubberen_Robbie
Rubbergate
Rubberism
Rubberist
Rubberneck
Rubberneck
Rubbernecking
Rubbers
Rubberstamp
Rubberstamp_(politics)
Rubbery_Figures
Rubbery_figures
Rubbery_polymer
Rubber_(baseball)
Rubber_(disambiguation)
Rubber_and_PVC_fetishism
Rubber_baby_buggy_bumpers
Rubber_ball
Rubber_band
Rubber_band
Rubber_Band_Grenade
Rubber_band_ligation
Rubber_Bowl
Rubber_bridge
Rubber_bullet
Rubber_bullets
Rubber_bullet_gun
Rubber_bung
Rubber_bung
Rubber_Bungs
Rubber_cement
Rubber_City
Rubber_Duck
Rubber_duck
Rubber_Duckie
Rubber_duckie
Rubber_ducky
Rubber_fetish
Rubber_fetishism
Rubber_hose_cryptanalysis
Rubber_hound
Rubber_hound
Rubber_mallet
Rubber_mixing
Rubber_necking
Rubber_plant
Rubber_Soul
Rubber_Soul
Rubber_soul
Rubber_stamp
Rubber_stamps
Rubber_stamp_(politics)
Rubber_stamp_legislature
Rubber_tired_metro
Rubber_tired_metro
Rubber_tree
Rubber_Vine
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