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What is
latex and Where does it come from?
Latex is rubber
and rubber is latex.
Latex is a
mixture of organic compounds produced by some plants in special cells
called caticifers. The composition of latex differs from plant to plant.
Most natural rubber comes from a single species of tree, Hevea brasiliensis.
Though native to South America, H. brasiliensis is planted in large plantations
in southeast Asia, including Malaysia.
Picture
of a rubber tree (taken from: www.csdl.tamu.edu/FLORA/imaxxeup.htm)
Rubber trees
take around 5 years to grow from a seedling to maturity, or a point that
it can start to produce rubber. It has an economic life of about 25 to
30 years. Trees are tapped by removing thin strips of bark, which disrupts
the laticifers (definition : A plant duct containing latex). The latex
then flows down grooves cut in the tree and drips into collection cups.

Rubber estate
workers (also known as tappers) then proceed to collect the latex from
the collection cups by pouring the contents of the collection cups into
a larger container before replacing the collection cup into its original
position.

After
natural latex is processed, it becomes a rubber with excellent mechanical
properties. It has excellent tensile, elongation, tear resistance and
resilience. It has good abrasion resistance and excellent low temperature
flexibility. However, without special additives, it has poor resistance
to ozone, oxygen, sunlight and heat. It has poor resistance to solvents
and petroleum products. Useful temperature range is -67º F to +180º F
(-55º C to +82º C). It is the high resistance to tear and its superb resiliance
over synthetic rubber that makes it still being used by medical doctors
and surgeons all over the world.
Some related links :
The Long
Road to Malaysia
In 1876, H.A.
Wickham brought seeds of the Hevea tree from Brazil to Kew Gardens near
London. After successfully cultivating these, seeds of these trees were
then distributed to India, Sri Lanka and Malaysia (then known as Malaya).

Rubber was
brought to Malaysia specifically to Kuala Kangsar, Perak in 1877 by Sir
Hugh Low, a British resident.

He brought
from the Kew Gardens nine rubber trees, marking the arrival of an industry
that would within decades put Malaysia prominently on the worlds map as
the largest producer of natural latex. (Is there unnatural latex?) More
information about how much latex Malaysia exports to the worls can be
found here : http://www.lgm.gov.my/nrstat/nrstatframe.html
Un-Natural
Latex
Un-natural
latex or un-natural rubber is called synthetic rubber. Developed in the
United States during World War II when supplies of natural latex was cut
off, the earliest synthetic rubbers were the styrene-butadiene copolymers,
Buna S and SBR, whose properties are closest to those of natural rubber.
SBR is the most commonly used elastomer because of its low cost and good
properties; it is used mainly for tires.
The use of
synthetic rubbers has since overtaken natural rubber by leaps and bounds.
But its usage is mainly in the non-medical industries, like the tyre industry,
which consumes 70% of the world's synthetic rubber production. Natural
rubber is mainly used in the medical industry because of its superior
properties.
Some related links :
Some Interesting
Facts and Figures
- Natural
Rubber comes from the Rainforest.
- Rubber gives
us surgical gloves, balloons, band-aids, sporting goods, tennis shoes,
and chewing gum.
- Natural
rubber resists heat. If you have ever flown in a aeroplane , you landed
safely on tyres made of natural rubber.
- Rubber trees
are among the taller trees in the rain forest.
- Just under
the bark of the rubber trees is a soft tissue that is rich with a creamy
liquid called latex. Slanting cuts in the bark of a rubber tree guide
the sap into a small cup which is then gathered by Rubber Tappers.
- Most Amazonian
rubber is still produced in the same way it was 100 years ago. The latex
collected in the forest is slowly dripped on a pole, which is turned
by hand in the smoke of a palm nut fire. The latex hardens to a tough,
rubbery mass.
- There can
be as many as six hundred wild rubber trees in one thousand acres of
rainforest. Because these trees are widely scattered in the forest,
they are more resistant to disease. When they are planted close together
in rows on rubber plantations, they are susceptible to a fungus called
the South America leaf blight.
- Rubber trees
must be about 5 years old before they produce latex.
- Wild rubber
trees grow throughout the forest and thrive only in these conditions
in South America.
- In Asia
plantations are possible without the danger of the leaf blight which
occurs in South America.
- Many indigenous
peoples earn their living in the Amazon through this rubber tapping
and through gathering other things like nuts, herbs and medicines, spices,
fruits, fish etc,. They do this without harming the delicate balance
of the rainforest.
- Rubber
tappers are called 'Seringueiros' - Say-rin-gay-eros. Today, the Seringueiros
maintain a higher standard of living than do the slash and burn farmers.
They have also lost only 4% of their forests.
- Chico Mendes
was the leader of the Tappers union and he survived 5 attempts on his
life. Chico Mendes defended the rubber tappers way of life. He was killed
at age 44 by gunmen hired by ranchers. Mendes organized a cooperative
and literacy campaign to help the tappers market and compete directly.
He formed the National Council of Rubber Tappers. The rubber barons
and bosses enslaved many indigenous peoples. When many tribes retreated
into the forest, they brought peasants into their camps and locked them
into a debt for goods scheme, similar to miners of that day. Tappers
who questioned authority were tortured or killed. in 1985, the rubber
tappers met and demanded better health care, education, credit, price
guarantees, research on sustainable forest products and a suspension
of tax breaks for ranchers and loggers.
- 'Extractive
Reserve' is the name given to land saved for sustainable forest gatherers.
Extractive Reserves allow residents families to collect rain forest
products, such as natural rubber and Brazil nuts. Sustainable rainforest
practices offer the solution to rainforest destruction.
- In Brazil,
more than 700,000 acres of land have been preserved through creating
these reserves.
- World rubber
consumption in 2004 was about 20 million tons. The figure is estimated
to keep rising. The vehicle sector, tyres and components together, use
about 70-75 % of the volumes mentioned above. Tyre industry is estimated
to grow at a slightly slower pace than other rubber industries. Most
of rubber products globally are consumed in North America, Western Europe
and Japan. The growth rate, however, is fster in China ond other countries
in the Asia-Pacific area
- Synthetic
rubber comprises about 60 % of the total volumes. Approximately 44 %
of synthetic rubber and 77 % of natural rubber are consumed by the tyre
industry. Of synthetic rubber types SBR (styrene butadiene rubber) is
the most used one. EPDM (ethylene propylene diene) has, however, a faster
growth rate. The fastest growing demand is experienced by thermoplastic
elastomers. These are materials with properties between traditional
rubbers and thermoplastic plastics.
Some related links :
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