There are two kinds of rubber: natural rubber harvested from the rubber tree and synthetic rubber produced from petroleum. Although synthetic rubber is widely used, natural rubber is always considered irreplaceable and “essential for the U.S. economy and national security because it provides performance characteristics not available from synthetic, petroleum-derived rubber,” according to the Program of Excellence in Natural Rubber Alternatives (PENRA), a R&D organization formed by the Ohio State University.
Rubber Tree (Hevea brasiliensis) is a tree belonging to the family Euphorbiaceae. It is the most economically important member of the genus Hevea. It is of major economic importance because the milky latex extracted from the tree is the primary source of natural rubber. (Wiki)