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The methods for ensuring long-term and safe operation of marine equipment due to comprehensive repair technologies that use epoxy oligomers and new compositions based on them are developed. The influence of temperature and UltraSonic Treatment (UST) on the rheological properties of the pure epoxy matrix and compositions based on it is explored. The compositions have different content of nanodispersed soot carbon black of brand PowCarbon 2419G (particle size of 24 ± 2 nm). It is established that when nanoparticle soot (q = 0.10…15.00 pts wt) is introduced into the composition of the epoxy matrix treated with ultrasound, the viscosity of the composition increases gradually. Based on the results obtained, temperature ranges are recommended, in which the viscosity of the studied compositions reaches optimal technological parameters for the effective impregnation of threads, tows and various fabrics, and which provide for the effective application of the composition to the working surfaces of marine equipment. Technical recommendations are given for applying the developed black-filled epoxy compositions to the working surfaces of parts, ship mechanisms and pipeline systems of marine vessels. First published online 28 January 2021

The effect of carbon black (CB) nanopowder on the electrical properties of polymer composite systems based on the epoxy resin is investigated using the method of impedance spectroscopy. It is established that the electrical and dielectric properties of the studied systems significantly depend on the nanofiller content. It is found that electrical conductivity and dielectric constant exhibit percolation behavior when the filler’s content increases. In this case, the electrical conductivity increases exponentially, indicating the formation of filler electrically conductive mesh inside the polymer matrix. A small jump in electrical conductivity when reaching the percolation threshold indicates the formation of indirect contacts between the particles. The value of the percolation threshold of conductivity is 8%. It is shown that the dielectric constant of epoxy nanosystems is almost unchanged in the frequency range of 102–105 Hz. It is related to the structural features of the filler particles, which ensure the existence of a minimal dielectric gradient between the matrix and the filler. It is found that the dielectric constant of the studied systems also shows percolation behavior. The obtained material based on the epoxy matrix is characterized by a high value of dielectric constant, which at a carbon black nanopowder content of 29% is 4680. This material is characterized by relative frequency invariance and a high value of dielectric constant, so it has great potential for practical application.