Stretch Armstrong keeps best at room temperature. Stretch Armstrong is made of latex rubber filled with gelled corn syrup, which allows it to retain shape for a short time before shrinking to its original shape. An estimated 67 different versions from Japan, Germany, Italy, France, Australia, and other countries released Stretch Armstrong variations between 1976 and the 1990s. The last two were filled with a granular solid in place of the viscous liquid found in the other figures. A vacuum pump, which attached to the heads of these figures, removed the air from within, which "froze" the toy in its stretched position.
Foam rubber Foam rubber Foam rubber (also known as cellular, sponge, or expanded rubber) refers to rubber that has been manufactured with a foaming agent to create an air-filled matrix structure. Commercial foam rubbers are generally made of either polyurethane or natural latex. Latex foam rubber, used in mattresses, is well known for its endurance. Polyurethane is a thermosetting polymer that comes from combination of Methyl di-isocyanate and polyethylene and some other chemical additives. Foam rubber was first produced in 1929 by Dunlop Rubber researcher chemists E. A. Murphy and Eric Owen using whipped latex. In 1937 isocyanate based materials were first