ABSTRACT
With the exception of sulfur, no material has increased the usefulness of rubbers as much as carbon black. The primary purpose for using carbon black with rubber is to reinforce it. By reinforcing is meant the enhancement of tensile strength, modulus, abrasion, and tear resistance obtained by adding the material. Physical properties of carbon blacks affect both rubber processing and vulcanizate properties significantly. Probably the most important property of a carbon black is the surface area that is accessible for reaction with rubber molecules per unit of weight, usually in square meters per gram. Although undoubtedly reinforcement is influenced by the chemical reactions between black and rubber, chemical properties of blacks are not of direct interest to the compounder. Thermal blacks are made by the thermal decomposition of natural gas in a preheated vertical furnace with a refractory brick lining and filled with a checkerboard pattern of silica brick.
