Molecular weight obtained by size exclusion chromatography and other chromatographic methods are not true determined volumes but are obtained via a calibration process which involves the preparation of a universal calibration curve relating log known molecular weight versus elution volume obtained for standard polymer fractions of precisely known molecular weight. Frequently standard polystyrenes are used for this purpose as these are easily available. If the molecular weight (MA) i of a species of polymer A is related to the molecular weight (M p/s)i of a polystyrene standard eluting at the same retention volume i.
KeywordsPolyethylene Polypropylene Turbidity Anhydride Styrene
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