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The uniaxial stretching of PP in the presence of PEOS was studied in the work. The deformation curves of PP obtained in air and PEOS are presented. Yield point of the polymer reduces on 15 % in PEOS at extension rate of 10-100 %/min that points to the formation of crazes inside PP. The curve of effective volume porosity versus a tensile strain obtained for PP in PEOS is shown. The plot of W(e) is increasing that is typically for delocalized crazing. For comparison the plot of PP upon it tensile drawing in isopropanol medium (delocalized crazing) is also presented. So we can easily fill PP matrices by PEOS using crazing mechanism. Further the peculiarities of acid (at HCl vapors) and basic (at NH3 vapors) hydrolysis of PEOS within nanopores of PP are considered. IR-spectra are proved that ethoxy-groups of PEOS transform to hydroxyl-groups during acid and basic hydrolysis. The band 960 sm-1 related to Si-OC2H5 disappears but bands 900-950 sm-1 related to Si-OH and 1630, 3350 sm-1 related to -OH appear in spectra after the hydrolysis. The degree of hydrolysis process was calculated using common gravimetrical procedure as the weight loss by a sample during replace of ethoxy-groups to hydroxyls. It equaled 85-90 %. Polymer-silicate composites obtained are hardness transparent films. Spherical particles with the diameter near 100 nm are discretely distributed inside a polymer film. Polymer-silicate composite films are characterized by a sharp anisotropy of mechanical properties respectively a direction of the preliminary elongation. After hydrolysis PEOS within polypropylene Young’s modulus of a polymer increases in 1.5-2 times. It was discovered that the surface of polypropylene films became hydrophilic. The wetting angle of sample surfaces after the hydrolysis decreased from 950 to 60-700 for a water drop. These composites show unusual sorption properties in relation to vapors of different low-molecular weight liquids (e.g. water, alcohol, ester, and others).