Efficiency and Mechanism of Antistatic Agent Action

As mentioned earlier, the addition of powdered metals to polymeric materials eliminates electrostatic charges on their surface. But electric properties of materials such as vulcanized rubbers filled this way are not stable for this reason, powdered metals are used only for polymer-based electroconducting varnishes [5,6] and adhesives [7]. In these cases, the powdered metals (Ag, Au, Ni, Al, Cu) are impregnated with epoxy resins or added to polyamides, PVC, silicones, etc. [1,5,8]. 

Electroconducting carbon blacks are largely utilized to increase the electric conductivity of organic polymers. The electric conductivity of carbon blacks depends on the following items  

The capacity to form branched or tentacular structures in the polymer matrix that are responsible for the electric conductivity this is the case for lamp, acetylene, and furnace carbon blacks [1]. 

The composition and the chemical structure of the surfaces of carbon blacks, since they can fix substances by chemical adsorption, thus creating insulating layers between particles. This makes impossible the formation of electroconducting structures. To prevent this problem the surface of the carbon black particles is cleaned by heat treatments in vacuum or in an inert atmosphere at 2000°C. 

The size and the size distribution of carbon black particles. At first, the specific resistance of the particles decreases with their size, and then increases by further diminution of the size. It is believed that a wide size distribution of particles favors the formation of branched structures of the carbon black in the polymer matrix. 

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