Investigation of copolymers of styrene and ethyl methacrylate by size-exclusion chromatography and gradient HPLC

Summary Copolymers of styrene and ethyl methacrylate (SEMA) have been separated according to composition by reversed-phase chromatography on C18 columns. The starting eluent was methanol, in which the copolymers are insoluble, and an elution gradient was formed by the addition of tetrahydrofuran, which is less polar than methanol yet a good solvent for SEMA copolymers. The method was applied to fractions obtained by size exclusion chromatography of model mixtures, and yielded a separation superior to that obtained in normal-phase mode on polar columns using gradients of increasing polarity.

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Untersuchung von Copolymeren von Styrol und Ethylmethacrylat durch Größenausschluß-Chromatographie und Gradient-HPLCII. Gradient-HPLC unter Umkehrphasen-Bedingungen

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Part I: see 1]