Chromatographic investigations of macromolecules in the critical range of liquid chromatography: 11. Polymer blend separation using a reversed stationary phase

The separation of blends of polymethacrylates was accomplished by liquid chromatography at the critical point of adsorption. Using a non-polar stationary phase and tetrahydrofuran-acetonitrile as the eluent, separations were conducted under chromatographic conditions, corresponding to the critical point of adsorption of the least polar component of the blend. After the separation step the blend components were precisely detected by an on-line capillary viscometer. The molar masses of the components were calculated from the viscometer signal via the corresponding Mark-Houwink relationship. At critical conditions for polydecyl methacrylate not only blends with a second homopolymer could be separated, but also blends where the second component was a blend itself. (C) 1998 Elsevier Science Ltd. All rights reserved.