## 3 Results
%) in secondary electrons (**a**) and the profile of the characteristic radiation distribution of the K\({}_{\alpha}\)S line (contrasted grafted film) and K\({}_{\alpha}\)C line along the cross-section of the sample (**b**). The red line is the path taken by the elemental analysis probe. Dotted vertical lines is microphotograph of the cross-section film obtained in the second electrons. The arrows indicate the defective areas in the grafted layers. Figure 3: Effect of DVB on the dependence of the ratio of optical densities of the absorption bands at 1492 and 1475 cm\({}^{-1}\) (D\({}_{1492}\)/D\({}_{1475}\)) in the transmission spectra (1) and multiple attenuated total internal reflection spectra (2–5) on the degree of grafting of PS on the PE film. [DVB], vol. %: 2—0; 3—0.25; 4—0.5; and 5—2.5. The micrographs of the surface of grafted samples (Figures 5 and 6) demonstrate the formation of spherical particles: cross-linked phases of PS, the average size of which varies in the range from 0.3 to 0.8 \(\upmu\)m, and their concentration reaches \(\sim\)5 vol. %. According to the local X-ray microanalysis data, the elemental composition of these phases does not differ from that of the composition of the dispersion medium; therefore, we assume that these dispersed phases belong to fragments of PS microgels cross-linked with DVB. These dispersed systems are observed in the films with both low (\(\Delta p\) = 34%) and high (\(\Delta p\) = 93%) degrees of grafting. Their concentration does not increase with an increasing degree of grafting. This suggests that DVB is consumed in the early stages of grafting polymerization. This is consistent with the fact that DVB is a more active monomer during its copolymerization with styrene [20]. The distribution of the grafted polymer over the thickness of the PE film can be determined based on the distribution of sulfur in the film after sulfonation. The graft polymerization of St on the PE film was carried out in [11; 19] under the same conditions as in the present work. In these works, it is shown that the surface layers of the films are enriched with PS. A similar pattern of the distribution of PS over the thickness of the PE film was observed in this work (Figures 4 and 7). Figure 5: Micrograph of the surface of the grafted PE film obtained using a scanning electron microscope. \(\Delta p\) = 67%, [DVB] = 0.5 vol. %. Figure 6: Micrograph of the surface of the grafted PE film obtained using a transmission electron microscope. \(\Delta p\) = 67%, [DVB] = 0.5 vol. %. The figure shows that the surface layers of the films are enriched with sulfur. The difference between the supramolecular organization of the sulfurized PE-PS-DVB film and the binary PE-PS system is the increased nonuniformity of the sulfur distribution, the presence in the volume and on the surface of microphase particles of cross-linked DVB having clearly fixed interfaces, and the formation of the contact zone of the grafted layer with the volume of the film of extended defects and cracks, arising as a result of the formation of internal stresses of thermochemical origin. (Figure 8). In our opinion, the nonuniformities of the sulfur distribution are the result of structural and morphological heterogeneities in the organization of the membrane films that occur during the graft polymerization of the monomer, and the participation of polymerization products in the formation of spatially cross-linked structures of macromolecules of the grafted polymer when their fragments lose translational mobility. This induces the microgel particles to spread and coalesce in their contact zone (Figure 9). Nevertheless, the graft polymerization process continues, and the final stage leads to a more uniform distribution of the grafted polymer over the entire thickness of the film (Figures 7b and 10). Figure 7: Distribution of sulfur over the cross-section of the PE film with grafted PS (\(\Delta p=90\%\)) (**a**) and the film with grafted PS in the presence of DVB (\(\Delta p=67\%\), [DVB] = 0.5 vol. %) (**b**).