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Publicly Available Published by De Gruyter January 1, 2009

Dispersity in polymer science (IUPAC Recommendations 2009)

  • Robert F. T. Stepto


This recommendation defines just three terms, viz., (1) molar-mass dispersity, relative-molecular-mass dispersity, or molecular-weight dispersity; (2) degree- of-polymerization dispersity; and (3) dispersity. "Dispersity" is a new word, coined to replace the misleading, but widely used term "polydispersity index" for Mw/Mn and Xw/Xn. The document, although brief, also has a broader significance in that it seeks to put the terminology describing dispersions of distributions of properties of polymeric (and non-polymeric) materials on an unambiguous and justifiable footing.

Project Year: 2008, Project Code: 2008-022-1-400


1. IUPAC. Compendium of Polymer Terminology and Nomenclature (the "Purple Book"), prepared for publication by R. G. Jones, J. Kahovec, R. Stepto, E. S. Wilks, M. Hess, T. Kitayama, W. V. Metanomski, with advice from A. Jenkins and P. Kratochvil, RSC Publishing, Cambridge, UK (2008); Chap. 3.Search in Google Scholar

2. (a) The Shorter Oxford English Dictionary, 3rd ed., C. T. Onions, G. W. S. Friedrichsen (Eds.), Oxford University Press (1973);Search in Google Scholar

2. (b) The Pocket Oxford Dictionary of Current English, 6th ed., J. B. Sykes (Ed.), Oxford University Press (1978).Search in Google Scholar

Published Online: 2009-01-01
Published in Print: 2009-01-01

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