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Handbook of Size Exclusion Chromatography and Related ...

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just ignoring the fractionation <strong>of</strong> the sample in the PSS HighSpeed column. The<br />

HighSpeed SEC separation took about 3 min. The viscosity results <strong>of</strong> the SEC <strong>and</strong><br />

the FIA method agree within 2%. This example shows very nicely how much<br />

flexibility can be gained by using HighSpeed columns, which really separate the<br />

sample (in contrast to the delay columns in FIA methods that separate <strong>of</strong>f<br />

the solvent peaks only). If analyses are carried out in this way, the clients can decide<br />

post-run which results they need without having to repeat the actual analysis.<br />

5 CONCLUSIONS<br />

SEC separations can now be carried out 10 times faster than before (in about<br />

1 min) using specially designed HighSpeed SEC columns. They <strong>of</strong>fer similar<br />

resolution <strong>and</strong> can be run on existing equipment just by replacing a conventional<br />

column with a HighSpeed column one by one. This allows the opening up <strong>of</strong> SEC<br />

applications to new fields where results have to be in fast (as in in-line production<br />

control) or many samples have to be run (as in high-throughput systems) <strong>and</strong><br />

space, money, <strong>and</strong> staff are limited. Because HighSpeed SEC columns separate the<br />

samples they can be used for distribution reports (e.g., molar mass) <strong>and</strong>/or for the<br />

determination <strong>of</strong> property averages only (e.g., intrinsic viscosity or Mw), similar to<br />

FIA experiments.<br />

Because HighSpeed SEC columns are available in different packings they<br />

can be used in different solvents for different applications (including hightemperature<br />

applications). If sample separation is never required, then the FIA<br />

method can be used to obtain molar mass or viscosity averages determined on a<br />

similar time scale.<br />

ACKNOWLEDGEMENTS<br />

The author would like to thank his colleagues Dr. G. Reinhold <strong>and</strong> Dr. C. Dauwe<br />

from PSS who did the design, the optimization <strong>and</strong> testing <strong>of</strong> PSS HighSpeed<br />

columns. He would also like to thank PSS for allowing this work to be published.<br />

REFERENCES<br />

1. RB Nielson, AL Safir, M Petro, TS Lee, P Huefner. Polym Mat Sci Eng 80:92, 1999.<br />

2. S Brocchini, K James, V Tangpasuthadol, J Kohn. J Am Chem Soc 119:4553, 1997.<br />

3. E Meehan, S O’Donohue, JA McConville. Proc Intern GPC Symp 2000. Waters,<br />

Milford, 2001.<br />

4. WS Wong, M Haney, S Welsh. Proc Intern GPC Symp 2000. Waters, Milford, 2001.<br />

5. PJ Wyatt, T Scherer, S Podzimek. Proc Intern GPC Symp 2000. Waters, Milford,<br />

2001.<br />

© 2004 by Marcel Dekker, Inc.

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