Commonly Used Rubber Materials
Natural rubber is a polymer of isoprene and has a molecular weight of 100,000 to 1,000,000. Sometimes a trace of other materials such as proteins, resins, and inorganic materials are found in high quality natural rubber.
EPDM (Ethylene Propylene Diene)
A synthetic rubber and elastomer characterized by a wide range of applications. The E stands for Ethylene, P for Propylene, D for diene and M refers to its classification in ASTM standard D-1418.
NBR (Nitrile Rubber)
A family of unsaturated copolymers of 2-propenenitrile and various butadiene monomers (1,2-butadiene and 1,3-butadiene). Although its physical and chemical properties vary depending on the polymer's composition of nitrile (the more nitrile within the polymer, the higher the resistance to oils but the lower the flexibility of the material), this form of synthetic rubber is generally resistant to oil, fuel, and other chemicals.
SBR (Styrene Butadiene Rubber)
A synthetic rubber copolymer consisting of styrene and butadiene. It has good abrasion resistance and good aging stability when protected by additives, and is widely used in car tires, where it is blended with natural rubber. It was originally developed prior to World War II in Germany, but during the War was used extensively by the USA to replace natural rubber supplies from the far-east, that had been captured by the Japanese.
A polymer containing silicon together with carbon, hydrogen, and oxygen. During manufacturing, heat is required to vulcanize (set or cure) the silicone into its rubber-like form. This is normally carried out in a two stage process at the point of manufacture into the desired shape, and then in a prolonged post-cure process. It can also be injection molded.
Polyisobutylene (in the form of polyisobutylene succinimide) has interesting properties when used as an additive in lubricating oils and motor fuels. Polyisobutylene added in small amounts to the lubricating oils used in machining results in a significant reduction in the generation of oil mist and thus reduces the operator's inhalation of oil mist.
Largely used in various parts of automobile tires. Its use in the tread portion of giant truck tires helps to improve the abrasion, i.e. less wearing, and to run the tire comparatively cool, since the internal heat comes out quickly.