Аннотация:A nanocomposite based on high-density polyethylene with 13–15 wt % of barium titanate wasobtained by the low-temperature synthesis of the inorganic component directly in the mesopores of an oriented polymer matrix using the sol-gel method followed by hydrothermal treatment in an alkaline medium.Crystallization of barium titanate in nanopores was detected by X-ray powder diffraction and electronmicroscopy to occur mainly in a cubic crystalline modification with an average crystallite size of 16 nm,where crystallites form chain structures. The dielectric properties of the polymer nanocomposite and bariumtitanate synthesized under similar conditions were comparatively assessed