We performed 3 simulations with the water content of 3, 6, 12, and 17 wt %. 12% wt approximately corresponds to the saturation. The total number of beads was about 67,000. At the water content of 3 wt%, we observed formation of separated hydrophilic clusters, containing water and sidechains. At higher water contents, a continuous hydrophilic subphase was formed. No particular segregation morphology in any of the systems was detected. However, the tessellation analysis shows that the hydrophilic subphase is comprised of a three-dimensional network of irregular channels of the average diameter of 2, 2.5 and 3 nm at 6, 12 and 17 wt% of water, respectively. With the increase of the water content a percolation-type transition from the system of isolated hydrophilic clusters to the three dimensional network of irregular channels forming a hydrophilic subphase. The modeling allows one to estimate the structural parameters (volume fraction or porosity, surface area, channel diameter) and the transport coefficients (permeability, conductivity) in the hydrophilic subphase. Also, it is possible to mimic SAXS, SANS, and NMR experiments to discriminate the structural models used for interpretation of the experimental data.
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