Advertisement

Chromatographia

, Volume 10, Issue 2, pp 75–78 | Cite as

Allowance for polydispersity in the determination of the true plate height in GPC

  • J. H. Knox
  • F. McLennan
Originals

Summary

In gel permeation chromatography (GPC), dispersion of a sharply injected sample arises both from the polydispersity, P, of the polmer sample and from the kinetic processes occurring within the column. The latter are described by the true plate height, H. It is shown that a current formula for deriving H from the observed band dispersion and the polydispersity is incorrect and that for samples with P≤1.1 a good approximation is H=Happ-L(P-1) (1+α)/x2 where Happ is the apparent plate height calculated in the normal way from the experimental peak width and retention time or volume; L is the column length; α is a correction term whose value is 0.4 for P=1.10; x is a measure of the relative molecular mass range covered by the packing material (x generally lies between 4 and 12 for GPC materials of narrow pore size distribution). It is concluded that the true plate height cannot generally be obtained from the elution peak of a polymer standard whose polydispersity is much larger than about 1.01.

Keywords

Molecular Mass Pore Size Distribution Mass Range Correction Term Peak Width 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. [1]
    J. C. Giddings, “Dynamics of Chromatography Part 1” Marcel Dekker, New York, 1965.Google Scholar
  2. [2]
    L. R. Snyder andJ. J. Kirkland “Introduction to Modern Liquid Chromatography”, John Wiley, New York, 1974.Google Scholar
  3. [3]
    D. D. Bly, J. Polym. Sci., A-1 6, 2085 (1968).Google Scholar
  4. [4]
    D. D. Bly, Analyt. Chem.41, 477 (1969).Google Scholar
  5. [5]
    K. K. Unger, R. Kern, M. C. Ninou andK. F. Krebs, J. Chromatog.99, 435 (1974).Google Scholar
  6. [6]
    K. K. Unger andR. Kern, J. Chromatog.122, 345 (1976).Google Scholar
  7. [7]
    H. W. Osterhoudt andL. N. Ray, J. Polym. Sci. C21, 5 (1968).Google Scholar
  8. [8]
    W. A. Dark andR. J. Limpert, J. Chromatog. Sci.11, 114 (1973).Google Scholar
  9. [9]
    J. J. Kirkland, J. Chromatog. Sci.10, 593 (1972).Google Scholar

Copyright information

© Friedr. Vieweg & Sohn, Verlagschesellschaft mbH 1977

Authors and Affiliations

  • J. H. Knox
    • 1
  • F. McLennan
    • 1
  1. 1.Department of ChemistryUniversity of EdinburghUK

Personalised recommendations