Caoutchouc

Caoutchouc (also called “India rubber,” regardless of its source) is a natural rubber that is the first-processed form of the latex of certain trees and plants, particularly the rubber tree (Hevea brasiliensis), the white rubber vine (Landolphia spp.), and the Ceara rubber tree (Manihot carthagenesis).  It is the precursor to fully-processed rubber. It is distinguished from other varieties of natural rubber by the proteins it contains, which can cause allergic reactions in some people. Caoutchouc is used extensively in many applications, and is valued for its large stretch ratio, high resilience, and for being extremely waterproof.

The best-known source of natural rubber is the rubber tree (Hevea brasiliensis).  Native to Central and South America, archaeological records indicate that the latex of the rubber tree was first used by the Olmec civilization to make rubber balls used for the Mesoamerican ball game.  Rubber latex was introduced to Europe in the 18th century.  It’s usefulness was quickly recognized and exploited, with plantations appearing in several tropical colonial holdings in Indonesia, India, and the Congo.

In the Congo, the Belgian colonial rubber industry was based on harvesting the latex of the white rubber vine (Landolphia owariensis). By the turn of the 20th century, the rubber trade in the Congo had become notorious for its brutal treatment of the local people, who were often conscripted against their will and subjected to harsh penalties (including death) for not meeting production quotas.  Joseph Conrad’s masterpiece of literature Heart of Darkness was based heavily on Conrad’s experiences in the Belgian Congo.

Today, synthetic rubber is a widely-used alternative to natural rubber that avoids the allergenic nature of caoutchouc.  However, natural rubber is still a valuable industry, with most of the rubber today produced by plantations in Southeast Asia, Central and West Africa, and South America.

The history of natural rubber has many fascinating chapters, form the Mesoamerican ballgame to the saga of Congo rubber, to the invention of vulcanized rubber tires and Henry Ford’s dream of a Brazilian rubber plantation utopia, and beyond.  The usefulness of caoutchouc lives on in thousands of everyday products in home and industry around the world.

Featured photo credit: Harvesting the white rubber vine (Landolphia owariensis), circa 1906.  Courtesy Wikimedia Commons.