Resolution and fractionation in gel permeation chromatography

Abstract Formulas are developed for describing resolution in gel permeation chromatography (GPC) in polymer analysis. Simple caluclations permit easy determination of the effect of variables on the resolution. Through the use of two characterized polymer samples the specific resolution Rs can be calculated. From the specific resolution the percent of fractionation between any two or more populations can be predicted or, conversely, a GPC curve can be analyzed for the component molecular weights and molecular weight distributions MWD and then the per cent fractionation between the components calculated. This is especially useful in preparatory scale separations and purifications. The principle of the constancy of width divided by polydispersity, W/d is developed and used to demonstrate a very simple method of determining the polydispersity of a sample.