Carbon black is a graphitic carbon in composition, which is similar to graphite. Carbon black exhibits electrical conductivity and has low electrical resistance. Although the conductivity of carbon black is not the best, it is favored by manufacturers for its cheap advantage and can be applied in many fields.
The conductivity of carbon black depends largely on the microstructure of carbon black, and the conductivity of graphitized carbon black is high. The electrical conductivity is also directly related to the structure of carbon black.
Generally speaking, the smaller the particles, the better the conductivity, mainly because the number of carbon black particles per unit volume increases, the distance between particles decreases, the resistance decreases, and the conductivity increases.
The structure of carbon black is also an important factor affecting the conductivity. The conductivity of high-structure carbon black is better than that of low-structure carbon black, mainly because the fiber structure of carbon black interweaves to form more conductive paths. Generally, the oil absorption value is commonly used to indicate the structure of carbon black. The larger the oil absorption value, the higher the structure of carbon black, the easier it is to form a conductive path, and the structure is stable and not easily damaged.
Basically, all carbon blacks are conductive, but the conductivity of certain carbon blacks is not outstanding enough. Manufacturers can develop carbon black with strong conductivity according to requirements. At present, according to the conductivity of carbon black, it is divided into: ordinary carbon black, conductive carbon black, superconductive carbon black, special conductive carbon black, and its conductivity increases in turn.
Generally speaking, the conductivity of carbon black is not the best, but many manufacturers choose carbon black as a conductive agent based on their willingness. However, some users also reported that the effect of using conductive carbon black is not good. The editor believes that among the many factors affecting carbon black, dispersibility is also a decisive factor. When we choose carbon black with high electrical conductivity, the basis is that the expected effect cannot be achieved. At this time, the dispersibility of carbon black plays a role. As long as the dispersibility of carbon black is solved, the electrical conductivity can be improved.