Determination of the width of a narrow molecular weight distribution by gel‐permeation chromatography

Abstract

synopsisA recycle gel-permeation chromatography (GPC) method for extrapolating to infinite resolution is proposed. From the GPC calibration curve, the extrapolated elution peak width volume can be converted into peak width in decades of molecular weight. For an essentially Gaussian distribution, the weight-average/number-average molecular weight ratio can be determined from a calculated conversion table.

Size-exclusion chromatography—a review of calibration methodologies

“…Two ''classical'' methods of note are the reversed-flow [82] and recycle [83] techniques, both of which are rather demanding experimentally. In the former, more commonly used method, a sample is injected into the instrument in the normal way, but when the sample peak is halfway through the column, the flow is reversed.…”

Large scale preparative gel permeation chromatography

“…Once again, the widest distribution within the fractions occurred at the ends of the molecular weight distribution, the values ranged from 1.25 to 1.47. Waters [9] has recently shown that the process of recycling, whereby the polymer is passed repeatedly through the same gel, offers considerable scope for improved fractionation efficiency.…”

Calibration procedures in gel permeation chromatography

“…to find unique values of s and t. Equations (9), (10) and (11) give a linear molecular weight calibration for a broad molecular weight distribution fraction over its elution volume range, and from equation (3) and the peak elution volume Mpesk can be calculated. Balke et have described a search technique for the determination of a linear calibration curve from the gel permeation chromatogram of a broad molecular weight distribution fraction.…”