A detailed discussion of the influence of the amount of deposited polymer on the retention properties of polymer-coated silicas

Problems of the modification of the surface of micro-spherical silica gel with layers of polymer and the influence of the quantity of the coated polymer on the chromatographic properties of the resulting sorbents have been considered. The polymer modification of the surface of wide-pore micro-spherical silica gel obtained by means of hydrothermal treatment of the meso-porous silica gel under autoclave conditions is described. The polymer layer itself is formed by an octadecylmethacrylate-methylmethacrylate co-polymer. As a result, packings for RP-HPLC were obtained. An increase of the capacity factor (k) has been observed with an increase of the quantity of the polymer deposited during the polymer modification process. The indicated phenomenon depends on the increase of the number of C18 groups in the packing.