Reversed-phase separations of high-molecular-weight polystyrenes in a dichloromethane-acetonitrile solvent system

High-resolution separation of polystyrenes ranging from monomer and oligomers to the high-molecular-weight polymers ( > 900 000 dalton) has been achieved in a single gradient separation on a variety of small-pore-size reversed-phase columns. Separation of the high-molecular-weight polymers in the acetonitrile-dichloromethane solvent system appeared to be based on retentive interactions with the stationary phase, despite the fact that the polymers were nominally too large to enter the pores of the small pore size column.