## 2 Materials and Methods
### Characterization  
Transmission electron microscopy (TEM) of carbon nanotubes was carried out using JEM-2010 (JEOL) microscope. The defectiveness of carbon materials was studied using a T64000 Horiba Jobin Yvon Raman spectrometer (\(\lambda\) = 514 nm). Each time, before recording the spectra from the samples, a test spectrum from monocrystalline silicon was recorded. This made it possible to calibrate the device both in the position of the frequencies (the frequency of the long-wavelength optical phonon in silicon is well known and equal to 520.6 reciprocal centimeters) and in the intensity of signals. The spectrometer T64000 and argon laser are highly stable and reproducible. The monochromator used standard gratings for the visible range--1200 lines per millimeter. All Raman spectra were excited with a 514.5 nm Ar\({}^{+}\) laser line in the back-scattering geometry. A triple spectrometer T64000 Horiba Jobin Yvon with micro-Raman setup and CCD multi-channel detector cooled by liquid nitrogen was used. To avoid local overheating of the samples, the laser beam was slightly unfocused (diameter of spot was about 10 micrometers, the laser power reaching the sample was about 1 mW). All spectra were measured at room temperature. The spectral resolution was not worse than 1.5 cm\({}^{-1}\). Integration time was 10 s, 6 signal accumulations were made at each point. Morphology of the surface of the samples obtained was investigated with a S-3400N (Hitachi) scanning electron microscope (SEM) without sputtering. Textural characteristics were evaluated using a Nova 1200e analyzer (Quantachrome). The weight distribution of particles was carried out with a Microsizer 201 (VA Instruments) laser analyzer of particles. Investigation of chemical composition of surface of the samples was performed using X-ray photoelectron spectrometer (SPECS Surface Nano Analysis GmbH, Germany). Spectrometer was equipped with the PHOIBOS-150 hemispherical analyzer and the source of X-ray radiation XR-50M with Al/Ag anode. Al K\(\alpha\) (hv = 1486.74 eV) monochromized radiation was used. Thermal behavior at the heating of the prepared epoxy composites from 20 \({}^{\circ}\)C to 700 \({}^{\circ}\)C was studied using the thermal analyzer STA 449C Jupiter (Netzsch, Germany). The thermogravimetric (TG) analysis and differential scanning calorimetry (DSC) were carried out at the heating rate of 10 \({}^{\circ}\)C/min in air (25 sccm). Samples of approximately 5 mg were placed in an Al\({}_{2}\)O\({}_{3}\) crucible with a lid. The samples used for thermal analysis were slightly ground to powder in mortar for all the experiments, to obtain a homogeneous powder and provide uniform heating of the sample in a crucible. The hardness was measured using the Shore D hardness test. The sample was placed under the indenter, and then the pressure was applied, such that the indenter comes into contact with the sample. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Sample Code** & **Epoxy Resin** & **MWCNTs** & **EG** \\ \hline E0 & 100 & 0 & 0 \\ E/0.01 MWCNT & 100 & 0.01 & 0 \\ E/0.05 MWCNT & 100 & 0.05 & 0 \\ E/0.1 MWCNT & 100 & 0.1 & 0 \\ E/0.5 MWCNT & 100 & 0.5 & 0 \\ E/0.5 EG & 10 & 0 & 0.5 \\ E/1.0 EG & 100 & 0 & 1.0 \\ E/1.5 EG & 100 & 0 & 1.5 \\ E/2.0 EG & 100 & 0 & 2.0 \\ E/2.5 EG & 100 & 0 & 2.5 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Formulations of epoxy composites (wt.%). The test was conducted according to ASTM D2240 at 25 \({}^{\circ}\)C. Ten samples of each filler and its loading were taken for testing. The flammability of the prepared epoxy composites was studied according to the standard method of experimental determination of the ignition temperature of solid substances and materials was used in accordance with the national standard of Russian Federation GOST 12.1.044-89 (ISO 4589-84) \"Occupational safety standards system. Fire and explosion hazard of substances and materials. Nomenclature of indices and methods of their determination\".