Surface Energy Aspects of Carbon Black

In addition to specific surface area and the fractal nature of carbon black as discussed above, it may be expected that rubber-filler interactions, which are the roots of reinforcement, somewhat depend upon the surface activity of the particles. The so-called surface activity is not however a clearly defined concept as many phenomena might be involved, from Van der Waals proximity forces (around 4 kj/mole) to specific chemical interactions (e.g., hydrogen bonding, 20 kj/mole ionic bonds, 30 kj/mole). Despite the considerable literature on the subject, there is so far no standard method to measure siuface activity. 

Chemical fvmctions detected on (lamp and gas) carbon black surface. 

It is thus well established today that carbon black surface chemistry plays a very minor role, is any, in the reinforcement of general purpose elastomers. 

An attempt to quantify the role of filler surface chemistry is to consider the so-called surface activity, generally assessed through the surface energy Ys, which consists of two main components, i.e. 

New equilibrium gas adsorption techniques were recently used to analyze the surface energy distribution of carbon blacks. By deconvoluting the 

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