Title: linear constitutional repeating unit
Long Title: IUPAC Gold Book - linear constitutional repeating unit
DOI: 10.1351/goldbook.09622
Status: current

Definition
Constitutional repeating unit connected to exactly two other constitutional repeating units.

Notes
1) A linear constitutional repeating unit may be connected to one or more end-groups.
2) End-groups attached to non-terminal constitutional repeating units are sometimes termed side groups. The use of the term side group in this meaning is not acceptable.

Related Term
- hyperbranched molecule (figure): https://goldbook.iupac.org//terms/view/09615

Source
- PAC, 2019, 91, 523. 'Nomenclature and terminology for dendrimers with regular dendrons and for hyperbranched polymers (IUPAC Recommendations 2017)' on page 532 (https://doi.org/10.1515/pac-2016-1217)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/09622/html
- json: https://goldbook.iupac.org/terms/view/09622/json
- xml: https://goldbook.iupac.org/terms/view/09622/xml

Citation: Citation: 'linear constitutional repeating unit' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.09622
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Accessed: 2026-07-28T05:45:13+00:00