## 3 Results and Discussion
### Morphological Analysis  
The SEM investigations of the 10L and 10 LMMT samples (Figure 9) confirm that covering the surface of the PA6 and the PA6/MMT composites with ten triple layers did not contribute to the formation of a regular structure. The deposition of ten triple layers on the surface of the composites resulted in a highly porous structure. The obtained microscopic images show numerous fibers with uneven distribution on the surface of the tested material penetrating each other. It should be noted that the LbL method may cause the partial reorganization of crystalline and amorphous phases on the surface. Figure 8: Comparison of the TG and MCC measurements by determining the heat of combustion as a function of temperature during the thermal decomposition of the PA6 samples (heating rate 1 \({}^{\circ}\)C/min): (**A**) the samples without nanofiller; and (**B**) the samples with nanofiller. Figure 9: SEM investigations of (**A**) the 15L and (**B**) the 15 LMMT samples with the magnification of 350\(\times\). It may lead to the formation of local polycrystalline anisotropic structures, visible in Figure 9A,B, built of interpenetrating micro- and nanofibers. However, greater surface coverage was observed for the composites containing MMT. Such observations could confirm the impact of the presence and distribution of the mineral filler on the deposition of appropriate layers. The reason for this could be the local and temporary generation of weak, secondary binding forces between the nanofiller particles dispersed in the matrix and the particles of the compound present in the applied solution or in polyelectrolyte dispersion. Microscopic observations confirm the supposition that the surfaces on which the formation of (even local) interwoven fibrous crystal structures was observed showed a tendency to protect the entire material against the destructive effects of heat, contributing, among other things, to the reduction of the maximum point of heat release rate (PHRR). The adsorption of the compounds constituting the solution and polyelectrolyte dispersions resulted in the unification of the Rt values (Table 6) of both the pure and montmorillonite-reinforced polyamide matrix. The value of this parameter for compositions 5L, 10L and 15L oscillated around 4.70, while 5 LMMT, 10 LMMT, 15 LMMT were about 3.60. The deposition of the triple layers the by the LbL technique on pure polyamide 6 significantly reduced the Ra parameter, which suggested an improvement in the quality of the obtained surface. The material became smoother, indicating that the triple layers filled the pores on the surface of PA6. In the case of the nanocomposite samples, the value of the parameter mentioned above did not significantly change concerning the reference material reinforced with montmorillonite. In addition, for these samples, the distances between the peak and the valley were the same as those determined for the reference materials. The analysis of surface roughness proved that the use of the LBL method resulted in the even adsorption of the polyelectrolyte solution and dispersions (roughness profile curves--Figures 10 and 11), contributing to a significant reduction in the plane unevenness in the case of the composite. The average value of the Ra parameter obtained by the REFMMT, 5 LMMT, 10 LMMT, 15 LMMT materials was about 0.23. According to the literature, it is the value that characterizes the surfaces after grinding and then polishing [41]. Thanks to the 3D mapping of the 15L (Figure 10) and 15 LMMT (Figure 11) sample surfaces, it was possible to determine the height of the triple layers applied. The blank film REF (PA6) had a thickness of 28. The application of the five layers 5L increased the material thickness to about 63. The application of another five layers to obtain 10L increased the thickness of the material to about 105. The treatment of the sample with subsequent layers to obtain 15L increased the thickness of the sample profile to over 145 (max 147.17 ).