In search for HPLC separation media with new surface chemistries, a styrene-based monomer, 2,3-epoxypropyl vinylbenzyl ether, containing reactive epoxide groups has been synthesized and copolymerized with divinylbenzene in a suspension polymerization. The process involves the use of size monodisperse particles that are swollen with monomer and then polymerized in the presence of a porogenic diluent consisting of a mixture of 4-methyl-2-pentanol and octane. The effect of concentration of divinylbenzene on the pore size distribution and the specific surface area of the resulting uniformly sized porous poly(2,3-epoxypropyl vinylbenzyl ether-co-divinylbenzene) beads has been studied. The epoxide groups of the copolymer have been hydrolyzed and the beads used for reversed-phase chromatography of both small molecules and proteins to show the effect of hydrophobicity of the matrix on the separation properties. Reversed-phase chromatography of alkylbenzenes follows the expected pattern while for proteins the hydrolyzed beads with the highest content of the crosslinking monomer exhibit a remarkable deviation from the predicted retention characteristics.