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Translated by P. CurtisThe aim of this work was to produce a new filler for polymers in which a low surface activity is combined with a high degree of structure and functionalisation of the surface, which will bring the processing properties of filled rubber mixes closer to the properties of rubber mixes with channel carbon black. The oxidation of specimens of low-dispersion, highly structured carbon black of grade OMCARB S820 was carried out using aqueous solutions of hydrogen peroxide of different concentration. Using a combination of methods, including X-ray diffraction analysis (D8 Advance diffractometer; Bruker, Germany) and transmission electron microscopy (JEM 2100 electron microscope; JEOL, Japan), we assessed the physicochemical properties and the form and the number of oxygen-containing groups (carboxyl, phenolic, lactone) on the surface of a particle of oxidised S820 in comparison with carbon black K354 (produced by the Khazar Chemical Plant, Turkmenistan) and semi-active furnace black N550 (produced by Omsktekhuglerod). The rheological characteristics (MDR 3000 vibrorheometer and MV 3000 viscometer; MonTech, Germany) and the physicomechanical characteristics (tensometer; Shimadzu, Japan) of rubber mixes filled with these blacks and of rubber compounds based on natural rubber were determined. The dynamic properties of the rubber compounds and the glass transition temperatures were determined on a DMA 242D instrument (Netzsch, Germany). Comparative data on the temperature dependence of the mechanical loss tangent (tg δ) of the rubber compounds showed that at temperatures of −60 and +60°C the greatest differences are possessed by rubber compounds with K354. At intermediate temperatures, the tg δ values for rubber compounds with the different fillers are similar. The new carbon black was advantageous with respect to the strength properties and dynamic characteristics of the rubber compounds, retaining the unique properties of composites filled with channel black.Carbon black grades currently produced do not always meet all the increasing user requirements regarding the properties of composite materials of different designation, and therefore attempts are being made to create functionalised modifications of them. Thus, in the production of rubber compounds, by using channel carbon black with a large number of oxygencontaining groups on the surface of its particles, an increase was observed in the intensity of its interaction with polymers having a low degree of unsaturation, such as butyl rubber, or having active functional groups [1]. High-temperature regimes for producing furnace grades of carbon black (over 1500°C in the reactor, 700-500°C after the reactor) are considerably higher than the temperatures of thermal degradation of the oxygen-containing functional groups: carboxyl groups (CGs), phenolic groups (PGs), quinone groups (QGs), and lactone groups (LGs). Therefore, the development of technologies for the low-temperature post-reactor oxidation of carbon black is an urgent task.

The aim of this work was to study the properties of carbon black CH85 of the OMCARB series and to compare them with the properties of standard carbon blacks N339 and N234. The morphological characteristics, the size distribution of the globules and aggregates, the surface area, the proportion of micropore area, the degree of branching of aggregates, and also the mechanical and chemical properties were measured and calculated. The average size of the aggregates of CH85 is greater than that of N339 and N234, and the aggregates have a more open and branched structure. The iodine adsorption by CH85 is practically the same as that by N339 and lower than that by N234. The low-hysteresis index calculated on the basis of structural data is much better for CH85. This opens up the possibility of using this type of carbon black for the development of elastomeric materials with low hysteresis.