Abstract: Detonation nanodiamonds (ND) are a unique representative of nanomaterials, which have been increasingly used in science and technology for 37 years. In many ways, the field of application of ND is determined by the dispersion of microcrystallites, the reactivity and aggregative state of powders of ND in various media. The research is based on the properties of industrial detonation products produced by CLL SPE “SIDAL”. Nanodiamonds obtained by the detonation of alloys of trotyl with hexogen (DNA) and pressed charges of hexogen with graphite (DALAN) in equal conditions of synthesis were compared. Evaluated characteristics are: the size of microcrystallites was investigated by X-ray analysis; elemental composition (C, H, N, O, ash content); thermal stability in air according to the TGA and DTA curves; specific surface area was evaluated by the BET adsorption method; particle size distribution of aggregates in an aqueous medium was done by laser diffraction. It is shown that the sizes of microcrystallites for DNA and DALAN are respectively 4.0-4.9 and 6.1-7.5 nm. According to elemental analysis, the carbon content in DNA samples is significantly lower than DALAN ones, the content of hydrogen and oxygen is higher, because of a more developed DND surface. Nitrogen is absent in the DALAN samples, which may be connected with different kinetic conditions for the nucleation and growth of ND microcrystallites. Reactivity and propensity for aggregation for DNA is higher than for DALAN. It was observed that there has been an exothermic effect during the combustion of samples for both DALAN and DNA in the temperature range 200-400 °C,on the DTA curve, without loss of mass on the TGA curve. These peculiarities can be explained by the presence of excess surface energy for ND obtained in strongly disbalanced conditions of detonation synthesis. In general, the current studies have shown that DNA and DALAN, obtained under equal industrial conditions, have significant differences in carbon and nitrogen content, microcrystallite size, reactivity and a tendency to form agglomerates.
Index terms: nanodiamonds, detonation synthesis, reactivity, microcrystallites, aggregates.