Currently ninety percent (90
%) of the natural rubber production globally emanates from
Southeast Asia and is produced from over 15.6 million acres
of cultivated land. The leading countries producing natural
rubber, in order of production volume, are Thailand, Indonesia,
Malaysia, Singapore, Vietnam, Cambodia and Myanmar. The
three largest of these, Thailand, Indonesia, and Malaysia,
produce 85% of the world's natural rubber. In the past,
Cambodia's rubber has been traded primarily through the
other Southeast Asian countries. With the collapse of the
rubber cartel, which controlled production volume and pricing,
a glut of natural rubber has stymied the sales of natural
rubber produced in Southeast Asia. Countries such as Thailand
and Malaysia are not as eager to acquire rubber from Cambodia
when they are having difficulty marketing their own natural
rubber. Thus Gateway Commerce International, Inc. can offer
natural rubber directly from Cambodia for the long term
and at a discount to the world rubber market.
Natural latex rubber is coagulated elastic latex, obtained
from the white, milky liquid known as latex that circulates
through small veins in the inner bark of certain trees (rubber
trees) native to tropical and semitropical regions of the
world. Since the early 20th century the chief source of
latex has been the Hevea brasiliensis (Euphorbiaceae family)
tree. It is a tall tree of softwood with high, branching
limbs and a large area of bark. The rubber trees are planted
in rows on rubber plantations that cover vast tracts of
land in Southeast Asia. The Hevea brasiliensis tree is indigenous
to South America but was adapted by English botanists for
Africa, India and Southeast Asia during the 19th century.
Although other varieties of rubber trees have been cultivated,
the Hevea brasiliensis is now responsible for includely
all of the commercial natural rubber production in the world.
The Hevea brasiliensis tree produces latex, which oozes
from cuts, injuries, or a tap located on the tree, as a
milky sap. Special cells of the rubber plant called laticifers
produce latex. In general, the latex has a biological function
in herbivore defense. These laticifers act as a reservoir
for biosynthetic materials and metabolic by-products. All
latexes are emulsions, aqueous suspensions of insoluble
materials, which include alkaloids, terpenes, resins, phenolics,
proteins, sugars, and long-chain hydrocarbons.
Harvesting the latex is accomplished when the bark of the
Hevea brasiliensis tree is partially cut through (tapped)
with a knife. This causes the latex to ooze from the wound
and dries to yield a rubbery film. The latex consists of
an aqueous suspension of small particles, about 0.5 micrometer
in diameter, of cis-polyisoprene, a linear rubbery polymer
of high molecular weight. The rubber content of the suspension
is about 30 percent.
Rubber trees are tapped about once every two days, yielding
a cupful of latex, containing approximately 50 grams (1.7
ounces) of solid rubber, each time. The standard method
of tapping is to score the tree with a knife for half the
circumference of the trunk, slanting the cut down from left
to right at an angle of 30 degrees starting at the highest
point convenient to the tapper. Each subsequent cut is made
immediately below its predecessor. Trees are often rested
for a period after heavy tapping. Production commences when
a tree is 5 or 6 years old and with proper management the
tree's useful life may extend to more than 20 years. The
trees can be cultivated at a density of 375 trees per hectare
(150 trees per acre), approximately 2,500 kilograms of rubber
can be produced per hectare per year (one ton per acre per
year). English botanists located in Singapore developed
most of the cultivation practices that are currently used
for natural rubber production at the turn of the 20th century.
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