Chemistry International Blank Image
Chemistry International Text Image Link to Chemistry International Blank Image Chemistry International Blank Image Chemistry International Blank Image
Chemistry International Blank Image
Chemistry International Blank Image
Chemistry International Text Image Link to Current Issue
Chemistry International Text Image Link to Past Issues
Chemistry International Text Image Link to Officer's Columns
Chemistry International Text Image Link to Features
Chemistry International Blank Image
Chemistry International Text Image Link to Up for Discussion
Chemistry International Text Image Link to IUPAC Wire
Chemistry International Text Image Link to Project Place
Chemistry International Text Image Link to imPACt
Chemistry International Text Image Link to Bookworm
Chemistry International Text Image Link to Internet Connections
Chemistry International Text Image Link to Conference Call
Chemistry International Text Image Link to Where 2B and Y
Chemistry International Text Image Link to Symposia
Chemistry International Text Image Link to CI Indexes
Chemistry International Text Image Link to CI Editor
Chemistry International Text Image Link to Search Function
Chemistry International Text Image Link to Information

 

Chemistry International Text Image Link to Previous Issue Chemistry International Text Image Link to Previous Page Chemistry International Text Image Link to This TOC Chemistry International Text Image Link to Next Page Chemistry International Text Image Link to Next Issue

Vol. 27 No. 2
March-April 2005

Making an imPACt | Recent IUPAC technical reports and recommendations that affect the many fields of pure and applied chemistry.
See also www.iupac.org/publications/pac

Characterization of Polyamides 6, 11, and 12. Determination of Molecular Weight by Size Exclusion Chromatography
(IUPAC Technical Report)


E.C. Robert, et al.
Pure and Applied Chemistry
Vol. 76, No. 11, pp. 2009–2025 (2004)

This report presents the results from IUPAC Working Party IV.2.2 of the global trial within the framework of IUPAC Commission IV.2, “Characterization of Commercial Polymers.” The results were compared on the basis of molecular weight obtained by size exclusion chromatography (SEC) using different techniques practiced in participating laboratories, the majority of which were materials suppliers. The practical methodologies used different solvents for the polymers, in particular, benzyl alcohol, 1,1,1,3,3,3 hexafluoropropan-2-ol and tetrahydrofuran; the latter solvent was used after chemical modification of the polyamides, in general with trifluoroacetic anhydride. Eight laboratories participated in the trial. The repeatability for molecular weight in each laboratory was good, whatever technique was used, the relative standard deviation averaged over all laboratories was around 3%. The deviations in distribution of molecular weights with different experimental methodologies were broader, but were reasonably good despite the diversity of methods. The differences in the distribution correspond to a confidence interval of about 30% in molecular weight.

www.iupac.org/publications/pac/2004/7611/7611x2009.html


Page last modified 11 February 2005.
Copyright © 2003-2005 International Union of Pure and Applied Chemistry.
Questions regarding the website, please contact edit.ci@iupac.org
Link to CI Home Page Link to IUPAC E-News Link to IUPAC Home Page