Performance of Carbon Blacks. Influence of Surface Roughness and Porosity
Abstract Porous blacks of high surface area can be produced without changing particle size either directly, in the normal furnace black process, or indirectly, in the laboratory by the air oxidation of a normal commercial and essentially nonporous HAF black raw material. Blacks of high surface area produced by the direct process are characterized by a retardation of rate of vulcanization, lower rebound resilience, and high electrical conductivity. Laboratory-prepared products of high area show cure retardation, but their electrically conductive and resilience properties show relatively little dependence on the degree of porosity and surface area. Bound rubber measurements, modulus, tensile strength, and abrasion properties of the laboratory-oxidized samples indicate an increase of reinforcement with increasing surface area.