## 3 Results and Discussion
It corresponds to the sample combustion and can be confirmed by the DTG curve due to the appearance of a high peak [53]. Figure 3 shows that the MWCNTs/PDMS composite decomposes at a much higher temperature than pure PDMS but not much lower than that of the unmodified carbon nanotubes. However, there is a slight initial weight loss at lower temperatures up to 500 \({}^{\circ}\)C, which can correspond to the depolymerization of PDMS. The thermal analysis results of the coating material can be observed in Figure 4. In the first step, from about 60 \({}^{\circ}\)C to 200 \({}^{\circ}\)C, the adsorbed water is removed. This is confirmed by the DTG peak at 99.1 \({}^{\circ}\)C and the DSC peak corresponding to the heat necessary to evaporate the water (endothermic process). Moreover, in the mass spectrum in Figure 5, a strong signal at m/z equal to 17 and 18 can be observed as well as wide peaks in the range of 3000-3400 cm\({}^{-1}\) in the FT-IR spectrum. The process in the range of 200-500 \({}^{\circ}\)C can be associated with decomposition of the surface methyl group due to hydrophobization by HMDS, which is confirmed by the peak in the FT-IR spectrum (Figure 5) in the range of 2800-3000 cm\({}^{-1}\). The combustion process of the material begins at a temperature above  
Figure 3: Thermal analysis of the MWCNTs, PDMS, and silica–MWCNTs/PDMS composite. 600 \({}^{\circ}\)C, which confirms the release of carbon dioxide in both spectra in Figure 5. This can be confirmed by the DSC curve, which shows the exothermic peak in the range of 600-700 \({}^{\circ}\)C. In the case of the coating, the effects of earlier PDMS depolymerization cannot be clearly observed because the filler is predominantly built in the bulk phase of the material. This will be confirmed also by the SEM images of the surface as well as the XRD analysis further in this paper. The total weight loss is equal to 12.35%, of which 2.68% is adsorbed water. This is a significant difference compared to the decomposition of the main filler component, carbon nanotubes with adsorbed PDMS. Thus, it can be concluded that the obtained composite coating is characterized by better stability and thermal resistance. The water contact angles (WCAs) on each sample are presented in Figure 6. On each real surface, the advancing contact angle is the highest one and the receding contact angle is the smallest contact angle possible to measure. [PERSON]'s contact angle is somewhere between them, and its experimental measurements are practically impossible [54; 55]. For this reason, in order to describe the wettability of the surfaces better, the equilibrium contact angles were calculated using [PERSON]'s approach [56]. Figure 4: TG, DTG, and DSC curves of the coating. Figure 5: Mass and FT-IR spectra of volatile products of the thermal analysis of the coating. The highest WCA, equal to 106.3 \(\pm\) 7.5 degrees, can be observed in the case of sample #8. As shown in Figure 7, this surface is also characterized by the largest contact angle hysteresis (8.5 \(\pm\) 4.1 degrees) and the smallest surface free energy (21.2 \(\pm\) 3.8 mJ/m\({}^{2}\)). This results from the method of applying the coating; the layer with the largest thickness and heterogeneity was obtained, which confirms its roughness parameters and the surface height map. The high standard deviations of the contact angles, contact angles hysteresis, and surface free energies indicate a wide physical and chemical heterogeneity of surfaces #7 and #8. Figure 1:0 Water wettability of the obtained coatings. Figure 1:1 Surface free energies of the obtained surfaces. Sample #4 has the largest contact angle (95.3 \(\pm\) 1 degrees) among the samples obtained with the dip coating. However, the difference in the withdrawal speed in the critical range does not affect the surface properties of the produced coatings significantly; the equilibrium contact angles of the corresponding samples only differ by about one degree.