Elastomer

What is this: it protects against water, makes wheels roll, can jump high and makes teachers despair? It is “rubber” – products manufactured from the milky sap of plants. This milky sap is called latex. It contains rubber, gutta-percha or chicle collected in the vascular systems of woody and herbaceous plants.

Columbus was first surprised to find springy bouncing balls made by indigenous South Americans. He brought news of the rubber tree (Hevea brasiliensis) from the Amazon basin to Europe. After tapping, the rubbery latex flows from the tree bark. With treatment from formic or acetic acid, it hardens and forms an elastic rubber.

Chewing gum is no modern invention! The Aztecs chewed chicle, the thickened sap from the bark of tropical sapodilla (Manilkara zapota). Today, most chewing gums are made of entirely synthetic ingredients.

Here you’ll find the tree on the side bed and chewing gum under every school bench! Do you have a rubber plant (Ficus elastica) at home?  Its name gives it away: it too contains sap with rubber.