Sample remaining in an ODS column after compositional fractionation of copolymers by high-performance liquid chromatography

Abstract High-performance liquid chromatography is very effective for the compositional fractionation of copolymers. Octadecyl-modified silica gel (ODS) has been used as a packing material for fractionation in the reversed-phase (RP) adsorption mode. In the compositional fractionation of the samples of copoly-(methyl methacrylate-styrene) by RP gradient elution through ODS column, it was found that small peaks were observed with blank elution just after the sample measurement and a perfect baseline was recovered after several blank elutions.