Polymer samples were separated by high performance liquid chromatography using adsorption mode. When a combination of non-polar eluent and polar station phase or of polar eluent and non-polar eluent is used with gradient elution of increasing a good solvent, copolymers, such as styrene-methyl mathacrylate and styrent-butadiene copolymers, were separated by chemical composition, polybutadienes were separated by isomeric structure. With this mode molecular weight effect is negligible. For polar stationary phase, crosslinked acrylonitrile on acrylamide gel was used and styrene or octadecy1 methactylate gel was used for non-polar one.
When other combinations were used, polymers were separated by GPC mode or phase separation mechanism with greater molecular weight dependence.