Term: excluded volume of a segment
https://doi.org/10.1351/goldbook.E02260

Definition:
The volume from which a segment of a macromolecule in solution effectively excludes all other segments, i.e. those belonging to the same macromolecule as well as those belonging to other macromolecules. The excluded volume of a segment depends on the Gibbs and Helmholtz energies of mixing of solvent and polymer, i.e. on the thermodynamic quality of the solvent, and is not a measure of the geometrical volume of that segment.

Source: Purple Book, 1st ed., p. 58 (http://old.iupac.org/publications/books/author/metanomski.html)

Citation: 'excluded volume of a segment' 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.E02260

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