India rubber

Kautschukplantage in Kerala (Indien)
india rubber plan days in Kerala (India)

india rubber (indian. cao = tree and ochu = tear) is a comprehensive term for flexible polymers, of which rubber is made. India rubber can be vulcanized, unvulkanisiert or before-vulcanized.

Some kinds of india rubber produced by plants are: Natural rubber, Balata, Chicle - rubber, Gutta-percha and Guayule india rubber. Natural rubber, from Latex of the india rubber tree (Hevea brasiliensis), is the economically most important of it. There are synthetic india rubbers, which take today about 60% off of the world-wide need, in many variants. In addition as india rubber also Faktis and Kautschukregenerate are understood.

Table of contents

history

Präkolumbi time

the peoples Mesoamerikas and the indigenen peoples Amazoniens used natural rubber in various way. The Mesoamerikani ball play with a full rubber ball is most well-known. Also its water-rejecting characteristic was well-known, so that material was coated with it and those Mayas are their feet in such a way with one limit durable Gummiüberzug to have provided.

The oldest well-known articles from india rubber originate from the time from 1600 v. Chr.

beyond Mesoamerika

the customer of the india rubber reached only few humans in Europe at the beginning of, about emperors Karl V., which got a aztekische ball play crew demonstrated by Hernán Cortés. Only by books the knowledge succeeded strengthened at the public. Thus Juan de Troquemadas described 1615 in „De la Monarquia Indiana “, like the Indians of articles made water-rejecting and the Conquistador Bernal Díaz delCastillo over approx. 1520 aztekische ball players. This report was discovered and published however only 1632 in a library in Madrid.

Charles Marie de La Condamine observed on a scientific expedition for those Paris Academy of Science from 1735 to 1745 in the Amazon area on which wayIndia rubber was used and described the indianische mode of production. This released further reports and the first European attempts with the new material : 1761 were found a solvent for firm india rubber, around 1770 developed the eraser, 1791 a first patented procedure of Samuel Peal in To lay on turpentine solved india rubber on fabrics, 1824 the first raincoat or Macintosh and the “Wellington of boat”. These early rubber boots, became by Arthur Wellesley, 1. Duke of Wellington in the England early 19. Century famous. Despite this and further successes was the material after howto use forwards only with difficulty, since it began with large heat to stick and with cold weather became brittle.

india rubber boom and crash

Charles Goodyear, in Scientific American Supplement NO. 787, 31. January 1891

after the invention of the procedure of the Vulkanisation in the year 1839 by Charles Goodyear, came it in the Amazon region in the years from 1839 to 1910 to an india rubber boom, which made the cities one from and for Belém the then richest regions of Brazil. At that time developed the Teatro Amazon in one from, which to 7. January 1897with La Gioconda of Amilcare Ponchielli opened and 364 km is enough for Madeira Mamoré railway (EFMM). This should transport india rubber from only with difficulty by ship attainable areas of Amazon until postage of the Velho, at the Rio larva Irish Republican Army. The railway connection became even in the contract of Petrópolis,between Bolivia and Brazil, mentions, since an extension of the distance was agreed upon there by the Brazilian Grenzstadt Guajará Mirim at the Río Mamoré into the Bolivian city Riberalta. This was however never built, since the india rubber boom ended before.

After india rubber in the form of rubber to oneimportant material became, gave it attempts of india rubber trees in Plantagen to breed. Only outside of South America their structure succeeded, so to the Englishmen in their colonies in Asia. 1876 had already smuggled the Englishman Henry Wickham approximately 70,000 india rubber seeds from Brazil in the British Ceylon (today Sri Lanka), butonly at the beginning 20. Century came larger quantities from Asia on the market. Further important india rubber producing country was at that time the Congo Free State under the rule of Leopold II., which with criminal methods the native ones forced to production. With these Plantagen outside of Brazilthe price could be pressed and the india rubber boom in Amazonien came to an end. The large need led during the First World War again to an upswing, but that was not from duration.

Beside the Brazilians also the British under the low price suffered,why it 1920 the Stevenson plan (EN: Stevenson plan) devised, an india rubber trust primarily debited to the largest consumer, that went to the USA. At this time the plan of Henry Ford india rubber developed in Brazil to cultivate. In the today's Fordlândia, in the municipality Aveiro,if Ford employed workers, but because of different difficulties, in the twenties up to 5000 for example strong infestation by the mushroom Microcyclus occurring in Brazil ulei, the project failed. <ref>“Ford's Obsession ton of Rubber. At Emperical Study OF irrationally Decision< /ref> 1934 gave it to oneto stabilize further attempt the price from india rubber to. (EN: Internationally Rubber regularization Agreement)

lack of india rubber during the world wars

during both world wars lost Germany the entrance to its sources of india rubber, whereby the search for alternatives was carried. In the First World War became from Fritz Hofmannmade of Dimethyl butadiene, so-called Methyl-Kautschuk, a rubberizing set.

Also during the Second World War india rubber became limited. This time not only for the European Axis powers but also for the allied ones, since the asiatic Plantagen had been conquered by Japan.

In Germany industrial union colors produced starting from 1935 inthe Buna works styrene butadiene india rubber. As raw material for example brown coal served and from the neighbouring Leunawerk came the necessary hydrogen in Schkopau.

Starting from 1940 the national US-American Rubber stored reserve company natural rubber, since the USA with an attack of Japan in Asia feared a delivery stop. Asthis then also arrived, began the USA starting from 1941 15 nationally financed factories for Buna india rubber to develop. The patents for Buna lay with the standard oil OF new jersey, which due to an agreement with the industrial union colors refused, the Buna patents for the American marketto release, on which a commission of inquiry accused „continued conspiracy of the company of one in favor of Germany “and Harry S. Truman on a press conference of „betrayal “spoke. The American congress decided the release of the Buna patents for America. In the year 1943 the US production of 185.175 tons exceeded „Government Rubber “for the first time thoseGerman production of 110.569 tons and could be increased up to the end of war still on over 730.000 tons. <ref>To yokes strive, the development of the synthetic rubber industry in Germany and the USA before and during the Second World War< /ref>

There were attempts to use other india rubber supplying plants.During the Russia campaign the armed forces captured Russian research material over the use of dandelion (Taraxacum kok saghyz Rodin) for india rubber production. <ref>Cultivation of dandelion for production by india rubber< /ref> There were to cultivate German plans 1944 on 120.000 hectares in Eastern Europe dandelion, there to these between 6% and 10%India rubber <ref>Useful plant data base dandelion< /ref> in the roots contained, which however because of the war process became impossible. In the USA Guayule (Parthenium argentatum) was examined during the Second World War as spare plant. <ref>Useful plant data base Guayule< /ref> Also here india rubber is primarily in the roots concentrated, with onePortion from 7% to 10%.

synthetic india rubber

around 1860 could destilieren Greville Williams from natural rubber Isopren and determine the sum formula C 5 H 8. Thus it made possible to manufacture Gustave Bouchardat 1879 synthetic india rubber during a process taking several months for the first time,in which it received from india rubber won Isopren with hydrochloric acid together to heated up and a rubber-like substance. Around 1900 J. placed. Kondakow from Dimethylbutadien the first full-synthetic india rubber ago and already 1909 could be given the first patent for the production of synthetic india rubber at Fritz Hofmann.By it with Bavarian in Leverkusen from 1915 to 1918 2,500 tons were manufactured.

The first economically usable synthetic india rubber was styrene butadiene india rubber (SBR), one 1929 emulsion polymer of butadiene and styrene, developed by walter support. 1930 developed Erich Konrad and Eduard Tschunkur butadiene acrylo nitrile rubber (NBR) and inthe USA developed with DuPont chloroprene rubber (CR), which is sold today as neoprene. In the USA developed 1942 silicone rubber and 1948 flurocarbon rubber. In the following years ever more were developed on special needs co-ordinated synthetic india rubbers.

natural rubber

Der Latex fließt unmittelbar nach dem Schnitt
of the Latex follows directlythe cut

the antique Mesoamerikaner did not know the curing, so that they reached the transformation from Latex to a rubber-like material by addition of tree and Pflanzensäften. <ref>http://www.sciencemag.org/cgi/content/abstract/284/5422/1988< /ref>

Natural rubber can be won in Brazil further only aufwändig as collecting tank product (Extraktivismus). Thisecologically perfect, lasting management offers a native independent, auskömmliche existence to many. (see also: Chico Mendes)

commercial form

natural rubber can be driven out as liquid, whereby it is later easily mixable. In addition the tree juice is locally thickened and stabilized with ammonia. Becomes natural rubberbefore-vulcanized, it remains nevertheless liquid.

Natural rubber can be sold also as firm material. In addition one coagulates the liquid (to coagulating bring). Then the damp material is washed, dried on different ways and brought in form. Some traditional commercial sorts are: „smoked sheets “(dried in the smoke), „airdried sheets “(smokeless dried), „pale crepes “(washed) and „brown crepes “(unwashed).

  • Crepe india rubber: The natural rubber with Natriumsulfit one coagulates. India rubber runs by grooved rollers and last follows some smooth rollers.
  • Sheet india rubber: The natural rubber becomes with weak ants - or acetic acid coagulates. That becomes subsequently,India rubber in a rolling mill in some millimeter thick and about a half meter broad smooth volume rolled and the last rollers stamps a characteristic sample.

After the separation into approximately 1 meter for a long time „sheets “or „crepes “, these are dried, sorted according to quality andas bundle of approximately 100 kg sells.

Today natural rubber, which was manufactured in national standardized procedures, occurs most frequently. These procedures are for example: Thai Tested Rubber (TTR), standard Indonesian Rubber (SIR) or standard Malaysian Rubber (SMR).

Also in form of a powder can natural rubber inthe sales to be brought

world production

the five most important producer countries of natural rubber are today Thailand, Indonesia, Malaysia, India and the People's Republic of China. The largest African producers are: The Ivory Coast, Nigeria and Liberia. The world production amounts to annual7,6 millions t (dry weight, 2003), about which 80% are exported. Principal clients are the USA, Japan, China, Germany and France.

The largest producers of natural rubber
rank country production (in Tsd. t) Country struggled production (in Tsd. t)
Acht Staaten produzieren über 88 % der weltweiten Erzeugung von Naturkautschuk
Eight states produceover 88% of the world-wide production of natural rubber
1 Thailand 3030 10 Brazil 96
2 Indonesia 1792 11 Sri Lanka 92
3 Malaysia 1000 The 12 Philippines 88
4 India 694 13 Guatemala 50
5 China 550 14 Kambodscha 46
6 Viet Nam 391 15 Cameroon 46
7 the Ivory Coast 123 16 Myanmar 36
8 Nigeria 112 17 Mexico 23
9 Liberia 108

Source: Trade paper - the world in figures (2005)

synthetic india rubber

major item: Synthetic india rubber

today is manufactured india rubber mainly synthetically by polymerization. It develops usually from styrene and Butadiene, other Rohstoffbasen are styrene acrylate, pure acrylate, vinyl acetate.

The polymer chains are usually composed of hydrocarbons. Chains on the basis of Silikonen or other connections are likewise possible.

world production

present amounts to the portion of the synthetic india rubber of the total requirement of india rubberabout 60%. 1998 were according to data internationally institutes for of the Synthetic Rubber of producer (IISRP) the conversion about 10.4 million tons, about which 70% went into the automobile industry. The turnover-strongest synthetic sorts are:Styrene butadiene india rubber (SBR), polybutadiene india rubber (BR), nitrile rubber (NBR), chloroprene rubber (CR) and ethyl propylene serving india rubber (EPDM). Forthe carpet industry important is styrene butadiene Latex (SBL) and for applications at temperatures up to 300°C silicone rubber (SI).

chemical structure

natural rubber consists of polymerized Isopren of extremely uniform structure (cis -1,4-Gehalt > 99 %); its middle molecular weight is extraordinarily high (about 2 million).

material property

Viskoelastische Dehnung <math>\varepsilon</math> von Kautschuk auf eine anliegende mechanische Spannung <math>\sigma</math>.
viscoelastic stretch <math> \ varepsilon< /math> of india rubber on a lying close mechanical stress <math> \ sigma< /math>.

The characteristics of india rubber change by the Vulkanisation substantially. In addition india rubber is usually used today as mixture.

Unvulkanisierter india rubber is viscoelastic, i.e., after the creationan outside Kraft the material stretches slowly up to its final stretch and decreases/goes back after switching Kraft off not completely into its original form. After the Vulkanisation india rubber shows two important elasticity ranges: At high temperatures the material is still viscoelastic, duringit at low temperatures a flexible behavior shows. If however the glass transition temperature is fallen below, india rubber becomes hard and brittle.

Vulcanized natural rubber is particularly flexibly (also at cold temperatures) and zugfest.

subsequent treatment

the india rubber mostly supplemental by fillers such as Russian,around z. B. to increase the abrasion resistance for motor-car tires, softeners, Faktis (mineral or vegetable oil with india rubber interlaced similar characteristics), cross-linking chemicals, ageing protecting agents, flame protection means and pigments or coloring materials. Further additions are possible depending upon requirement of the final product.

Both natural rubber and synthetic india rubber are vulcanized.

India rubbercan be processed to pore rubber, with which the flexible foam material can have opened void structure from completely closed to complete.

use

between 65% and 70% of the entire india rubber goes into production from motor-car tires.

Natural rubber can as exclusive polymer orin mixtures with synthesis india rubbers to be used. It is unfavorable that with contact with sunlight and/or. with UV light or with fats natural rubber to dissolve can.


The main fields of application are binders for the Papierstreicherei, the carpet back coating as well as dipping article such as z. B. thin gloves.

In up-foamed form becomes Latex for Mattresses and sponges uses. Also for PET bottles, in addition, in very thin films for condoms, gloves or ballons and in thicker films for the production of casting forms, TRUCK and PASSENGER CAR tire, engine store, as well as various rubber/metal connections.

Articles of clothing and other articlesfrom Latex, and/or. Rubber or similar plastics provokes the skin and other senses (smell, optics) in a special kind (warmth - cold weather, humidity, stress of the body forms) and serves thus the Gummifetischismus.

see also:

sources

<references/>

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