Epoxy composites filled with boric acid and natural zeolite with different percentage (1, 5, and 10 wt%) were prepared. Hexamethylenediamine and polyethylenpolyamine were used as curing agents. The prepared samples and starting materials were examined using the methods of thermal analysis and scanning electron microscopy. The parameters of thermal decomposition in argon were analyzed. The limiting oxygen index was calculated in accordance with Van Krevelen and Hoftyzer equation. The thermal characteristics of the studied composites depend on the filler content. The results showed that the incorporation of 10 wt% fillers both boric acid and natural zeolite significantly improved the thermal properties of the obtained composites.

Epoxy composites filled with 0.5 wt% of multi-walled carbon nanotubes (MWCNTs), 10 and 15 wt% of boric acid and sodium bicarbonate separately, as well as composites filled with a combination of MWCNTs-boric acid and MWCNTs-sodium bicarbonate were prepared. The thermal behavior of the prepared samples was investigated under heating in oxidative environment using thermogravimetric analysis. The hardness was measured using the Shore D hardness test. To evaluate the flammability of the samples, the ignition temperature and time-to-ignition were determined. It was concluded that sodium bicarbonate in the studied concentrations (10 and 15 wt%) is not appropriate for use as a filler capable of improving the thermooxidative stability and reducing the flammability of epoxy polymers. The improvement in the thermal properties can be achieved by using the combination of boric acid and multi-walled carbon nanotubes as fillers. The thermooxidative destruction of the samples filled with boric acid passes more slowly and more evenly via the formation of B2O3 as a result of its decomposition.

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Thermal stability of aluminum, iron and copper nanopowders, produced by electrical explosion of wire during heating in the air, was investigated in the work. Thermal analysis method was used for control of thermal stability for nanodispersed metals in heating in the air. It was shown, that after a long time of storage in air electrical explosion metal nanopowders have had extra active ones. Estimation of velocity of flame spreading in poured layer of the powders was carried out. Quality changes in investigated samples, happened for storage time, lead to increase of flame front length and its line velocity. The results of the researches could be used for diagnostics of fire danger of nanodispersed metals, also for selection of working regimes and provision of fire explosion safety for technologies which produce and apply of nanodispersed metal powders. Time-factor have not effected on criteria concerning the danger of the loads and have not changed its marking.

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