Term: block
https://doi.org/10.1351/goldbook.B00682

Definition:
A portion of a macromolecule, comprising many constitutional units that has at least one feature which is not present in the adjacent portions. Where appropriate, definitions relating to 'macromolecule' may also be applied to 'block'.

Related Terms:
1) macromolecule (http://doi.org/10.1351/goldbook.M03667).
2) constitutional units (http://doi.org/10.1351/goldbook.C01288).

Source: PAC, 1996, 68, 2287. 'Glossary of basic terms in polymer science (IUPAC Recommendations 1996)' on page 2298 (https://doi.org/10.1351/pac199668122287)

Citation: 'block' 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.B00682

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