ABSTRACT The characterization of the molar mass distribution of a polymer by size exclusion chromatography (SEC) using a single concentration detector is often hindered by the problem of an appropriate calibration for polymers of different chemical composition and/or structure. The availability of on-line absolute detectors, as a light scattering and a viscometer, overcomes the calibration problem and greatly increases the information content that can be obtained. The use of absolute detectors is particularly important in the characterization of complex polymers. Complex polymers exhibit several superimposed heterogeneities as for example molar mass, chemical composition and/or structure. As the properties of these important complex polymers are closely related to their architecture, there is a strong need for adequate methods of characterization. A multi-detector SEC system using a light scattering and a viscometer provides several distributions (molar mass, size and intrinsic viscosity) and information on the conformation of the macromolecules.
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