Term: constitutional heterogeneity
https://doi.org/10.1351/goldbook.C01283

Definition:
The variation in constitution from molecule to molecule in polymers with molecules uniform with respect to elemental composition. An example is a polymer composed of linear and branched molecules; another example is a statistical copolymer comprising two isomeric constitutional units.

Related Terms:
1) constitution (http://doi.org/10.1351/goldbook.C01282).
2) statistical copolymer (http://doi.org/10.1351/goldbook.S05955).
3) isomeric (http://doi.org/10.1351/goldbook.I03291).

Source: Purple Book, 1st ed., p. 52 (http://old.iupac.org/publications/books/author/metanomski.html)

Citation: 'constitutional heterogeneity' 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.C01283

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