Term: branching index
https://doi.org/10.1351/goldbook.B00726

Definition:
A parameter, g, characterizing the effect of long-chain branches on the size of a branched macromolecule in solution and defined as the ratio of the mean-square radius of gyration of a branched molecule, < sb2 >, to that of an otherwise identical linear molecule, < sl2 >, with the same relative molecular mass in the same solvent and at the same temperature, i.e. g = < sb2 > / < sl2 >.

Related Terms:
1) radius of gyration (http://doi.org/10.1351/goldbook.R05121).
2) relative molecular mass (http://doi.org/10.1351/goldbook.R05271).

Source: Purple Book, 1st ed., p. 51 (http://old.iupac.org/publications/books/author/metanomski.html)

Citation: 'branching index' 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.B00726

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