Method of calculating molecular weight distribution function from gel permeation chromatograms. II. Evaluation of the method by experiments

Abstract

SynopsisThe calculation scheme for correcting the broadening effect due to imperfect resolution on gel permeation chromatograms was compared with actual performances of a gel permeation chromatography (GPC) column. The experiment consisted of fractionating a high-density polyethylene on a GPC unit and then determining the chromatograms of the cuts collected. The chromatograms of the cuts were also computed from the starting chromatogram using experimentally determined resolution factors. The degree of agreement between the calculated and experimental chromatograms of the cuts shows convincingly that the previously proposed calculation scheme is satisfactory for the treatment of GPC data.

Theory of Multiple‐Detection Size‐Exclusion Chromatography of Complex Branched Polymers

“…The SEC signal S det (t el ) obtained at elution time t el using a detector of type ''det'' for a linear polymer is given by the Tung convolution equation: [42][43][44] …”

Characterization of the extremely high molecular mass polystyrene by gel permeation chromatography

“…mass range• From the constants of the Kuhn-Mark-Houwink (KMH) equation at 25°C for PS in THF K= 6.8x10-3dl/g, a = 0.766 (20) or in a binary mixture of MEK and MeOH, 89•0:11.0, K= 7.3x10 -2 dl/g, a = 0.5 (21), neglecting the interval of mol. masses and it also can, eventually, render impossible determination of the values of the resolution factor h by employing the reverse flow technique (22). This shows that the primary required effect of the application of the thermodynamically poor solvent or theta solvent as the eluent is obvious• The second required effect is that by On the other hand, formation of the ghost peaks at high elution volumes (17) prevented evaluating chromatograms of the reference PS samples in the range of low mol.…”

A “Systematic Approach” to TD‐GPC Data Processing with Band Broadening Correction

“…The ideal GPC columns can arbitrarily provide any degree of separation, but more importantly can be functionally controlled through a single parameter, σ g , to implement a precise magnitude of axial dispersion or band broadening into the instantaneous polymer solution exiting the last column. This dispersion is mathematically perfect, in the sense that the spreading of the polymer follows exactly the Tung Integral Equations . These are Equations through 4.…”