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Functional polymer-inorganic hybrid nanomaterials are very attractive because they combine the properties of the polymer matrix (low density, chemical inertness) and the second component of inorganic nature (electrical conductivity, sensory properties, etc.). One of the original methods for obtaining nanocomposites with high mutual dispersion of the components is solvent-crazing, which is a type of inelastic deformation of glassy and semi-crystalline polymers. Resently, we developed an approach for the preparation of polymer-silica nanocomposites using crazing for volume filling matrix by a liquid precursor (hyperbranched polyethoxysiloxane), which was further converted into SiO2 in the volume of nanopores directly . The structure of similar composites depends on the content of the second component: from discrete silica nanoparticles (up to 15 wt.% SiO2) to interpenetrating networks (more than 20 wt.% SiO2). Similar composites are promising as the materials with special (conductive, thermal, sensor, etc.) properties. However, such composite are easily converted to the materials with a structure of semi-interpenetrating networks. To do this, its is needed to heat above the melting point of the one component. In the present case, similar a component can only be a polyethylene (PE) matrix. Indeed, the thermal treatment of PE-silica composite at a temperature of 160oC leads to the significant structural rearrangements, while it depends on the environment (air, H3PO4, glycerol), wherein heating is carried out. During heating in liquid media PE melt migrates from volume of a composite to its surfaces. Simultaneously with bleeding of the polymer the liquid medium, which is well compatible with SiO2, fills the void creating in a volume. The method described allows to fill the composites by H3PO4 and proton-conducting membranes with a conductivity of about 3×10^-2 S/cm are received.