Gutta-percha, natural latex obtained from Palaquium gutta and several other evergreen trees of East Asia. The latex, collected by felling or girdling the tree, is allowed to coagulate and is t...

Pará rubber tree, large tree (Hevea brasiliensis) of the family Euphorbiaceae (spurge family), native to tropical South America and the source of the greatest amount and finest quality of natu...

Balata, nonelastic natural rubber obtained as a latex from the South American tree Manikara bidentata and from related trees. Its properties are similar to those of gutta-percha, and its proce...

Rabbitbrush, name for shrubby plants of the American genus Chrysothamnus of the family Asteraceae (aster family). They grow in arid regions of the W United States and in Mexico and are charact...

Caoutchouc, natural rubber obtained as a latex from various tropical plants, e.g., the Pará rubber tree. It is much more elastic than balata or gutta-percha. It is the most familiar and widely...

Chicle, name for the gum obtained from the latex of the sapodilla tree (Manilkara zapota), a tropical American evergreen. The sapodilla (known also by many other common names) is widely cultiv...

Hesse, Eva, 1936–70, American sculptor, b. Hamburg, Germany. Hesse's sculpture displays an antiformalism that developed in the late 1960s in reaction against conventional geometric constructiv...

Sapodilla, the edible fruit of Manilkara zapota (formerly Achras zapota), of the family Sapotaceae. The fleshy, brown fruit is the size of a small tomato, and has the flavor and texture of cin...

Butadiene, colorless, gaseous hydrocarbon. There are two structural isomers of butadiene; they differ in the location of the two carbon-carbon double bonds in the butadiene molecule. One (1,2-...

Formic acid or methanoic acid, HCO2H, a colorless, corrosive liquid with a sharp odor; it boils at 100.7°C and solidifies at 8.4°C. It has the lowest molecular weight and is the simplest of th...