Wet impregnation of pyrogenic silica (Aerosil 200 and Aerosil 300) with aqueous solutions of zinc salts [Zn(NO_3)_2, Zn(CH_3COO)_2, Zn(NH_3)_4(NO_3)_2 and zinc complexes with EDTA, ethylene diamine and diethyl triamine] was use to obtain a new type of dispersoids with "core-shell" (ZnO?SiO_2 systems) structure, containing 1-20% ZnO by weight, Physicochemical properties of ZnO/SiO_2 systems were determined using EDX, ICP, adsorptive static method and XRD.Wet impregnation allows to obtain ZnO/SiO_2 systems with the assumed ZnO content, regardless of the kind of zinc slat being supported (Table 4). Bulk and surface layer ZnO content is proportional to the amount of zinc salt being supported, and the surface layer is ZnO enriched 9Table 3). XRD shows that ZnO supported on pyrogenic silica is amorphous. Increase in ZnO content decreases ZnO/SiO_2 system specific surface (more visible in Aerosil 300), whereas their capillary structure remains unchanged (Table 6).Deposition of ZnO on pyrogenic silica improves its dispersion and ZnO/SiO_2 systems may be used as white fillers, crosslinking agents and activators of elastomer mixtures.
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