Chromatographic investigations of macromolecules in the “critical range” of liquid chromatography: I. Functionality type and composition distribution in polyethylene oxide and polypropylene oxide copolymers

Abstract

Polyethers obtained from ethylene oxide (EO) and propylene oxide (PO) and corresponding copolyethers were analysed by liquid chromatography under critical conditions (near the critical point of polymer adsorption) to obtain information on the functionality type distribution and structural inhomogeneity of copolymers. Homopolyether species were separated according to the number and type of their end groups. Copolymers of EO and PO (random and block) were split into groups depending on chemical composition, block length and the character of order in the monomer distribution. The experimental results are explained by considering the theory of polymer adsorption.