Term: constitutional unit
https://doi.org/10.1351/goldbook.C01288

Definition:
An atom or group of atoms (with pendant atoms or groups, if any) comprising a part of the essential structure of a macromolecule, an oligomer molecule, a block or a chain.

Related Terms:
1) macromolecule (http://doi.org/10.1351/goldbook.M03667).
2) oligomer molecule (http://doi.org/10.1351/goldbook.O04286).
3) block (http://doi.org/10.1351/goldbook.B00682).
4) chain (<em>in polymers</em>) (http://doi.org/10.1351/goldbook.C00946).

Source: PAC, 1996, 68, 2287. 'Glossary of basic terms in polymer science (IUPAC Recommendations 1996)' on page 2291 (https://doi.org/10.1351/pac199668122287)

Citation: 'constitutional unit' 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.C01288

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