Morphology and Particle Size Distribution of Sulfonated Сarbon Black

Modification of the surface of carbon black (CB) of the N326 is performed by treatment in an aqueous solution of sulfanilic acid with the addition of sodium nitrite. It is shown that the covalent modification of sulfonic groups in the amount of 0.25 up to 2.62 μmol/m 2 on the carbon surface does not result in any substantial change in the specific surface area (84–85 m 2 /g) and dibutyl phthalate absorption number of the aggregates of carbon black (of 70–76 cm 3 /100 g). A sample of CB with the density of coating with sulfonic groups of 2.62 μmol/m 2 is distinguished by the monomodal size distribution of carbon particles at an average diameter of about 250 nm and makes it possible to form highly stable aqueous suspensions.