 
Mask
Aspiring Postacrat
Username: Mask
Post Number: 17
Registered: 09-2002
Rating: 
Votes: 10 (Vote!) | | Posted on Friday, November 29, 2002 - 08:51 pm GMT: | 
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The story of Rubber.
(c) 2002 by Mask
The first description of the rubber tree, is due to an Explorer in the Brazillian forests a Pietro Martyre di Anghiera who first mentioned in Europe the exsistence of rubber.
Its the milky latex which is the Chief source of the natural Rubber ,this is obtained by makeing sloping cuts in the trunk. The Trees produce Latex from about the sixth year and reach full height about 2m in eight years.Many Tropical plants give off the white latex that contains the Rubber, of these the most productive is the Hevea brasiliensis also called Par'a Rubber (native to Brazil)
In 1839 the United states inventor Charles Goodyear discovered the techniques of Vulranization, which is a way of heating Rubber and Sulphur at a high tempreature to make it more stronger and elastic.
After Rubber established itself as a new wonder material and used in Waterproof garments and Machinery and Tyres, it had by the 1900 had become a valuable commodity and for a long time the Brazillian Goverment imposed limitations on the Rubber trade to ensure that an effective possesion could be maintained.But in 1876 an Englishman Sir Henry Wickham brought some seeds of a Hevea brasiliensis from the rain forests of Brazil to Kew gardens in London from this there Cuttings were taken to Sri - lanka and Malaysia ( both British Colonies at the time ) and where the destruction of substantial areas of Rain forests were destroyed to make way for rubber plantations and thus today 90 % of the worlds natural rubber is produced in Asia from the plants descended from the trees first proppogated using Wickhams seeds.Despite competition from Asia, Brazil at the start of the Century was still prospering from the Rubber exports which by the 1906 had reached 1,15000 tons a year. But such high levels of supply were not met by corrosponding levels of demand, the worlds market had become saturated prices plumeted ruining buissiness around the Globe throwing plantation workers out of work.
By 1912 captial invesment in both Asia and Brazil began to dry up , Brazil turned on its national debt and the threat of a World war
did not improve the problem, consequentley Brazil to other Industries.
In 1931 the first Natural synthetic Rubber was produced by a Gentleman with the name of Dupont,Natural Rubber which consists mainly of Polyisoprene and has a Chemical ecquasion of ( CH2 + CH2:C.CH3 : CH2) the Rubber is Coagulated from the Latex using acids and pressed into sheets.
The most commonest Synthetic Rubber today is ( S.B.R.) Styrene - Butadiene - Rubber this was Introduced during World War 2, it is made by the Emulsion Process in which Styrene and Butadiene are mixed in soapy water containing a catalyst.
S.B.R is now used in Tyres and is often mixed with natural rubber to Improve its resilence,Neoprene is used for protective Clothing and Electrical Insulation and Silicone is used for specialist users
An extract from the magic or rubber 1960, Author E .Joseph Dreany wrote: How will our lives be different in the Future as a result of rubber reasearch.For one thing mothers will not have to buy whole new wardrobes for their Children as they out grow their Clothes, Bathing suits could even be carried in a ladies purse and There will probally be dresses of the same material that can be worn by girls and woman alike.
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