Term: extraction fractionation
https://doi.org/10.1351/goldbook.E02306

Definition:
A process in which a polymeric material, consisting of macromolecules differing in some characteristic affecting their solubility, is separated from a polymer-rich phase into fractions by successively increasing the solution power of the solvent, resulting in the repeated formation of a two-phase system in which the more soluble components concentrate in the polymer-poor phase.

Related Terms:
1) polymeric (http://doi.org/10.1351/goldbook.M03667).
2) solubility (http://doi.org/10.1351/goldbook.S05740).
3) polymer-rich phase (http://doi.org/10.1351/goldbook.P04745).
4) power (http://doi.org/10.1351/goldbook.P04792).
5) polymer-poor phase (http://doi.org/10.1351/goldbook.P04744).

Source: Purple Book, 1st ed., p. 68 (http://old.iupac.org/publications/books/author/metanomski.html)

Citation: 'extraction fractionation' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.E02306

License: The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms.

Disclaimer: The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.