Natural rubber can be treated to make foam rubber and sponge rubber. The first synthetic rubber was made in Germany in World War I. Today synthetics, e.g., Buna S, neoprene, butyl, and nitrile, account for most of the world's rubber production. Made from Coal , Petroleum , Natural Gas , and Acetylene , synthetic rubbers are resilient over a wider Temperature range than natural rubber and are more resistant to aging, weathering, and attack by certain substances, notably, Oil , solvents, Oxygen , and Ozone . Silicone rubbers are used in insulation. Polyurethanes are used in tires, in shoes, and as foams.
Neoprene is used for making hose and tank linings.
Butyl rubber is used in inner tubes and as insulation.