Term: ladder macromolecule https://doi.org/10.1351/goldbook.L03441 Definition: A double-strand macromolecule consisting of an uninterrupted sequence of rings, with adjacent rings having two or more atoms in common. Alternatively, a ladder macromolecule is a double-strand macromolecule with constitutional unit joined to each other through four atoms, two on one side and two on the other side of each constitutional unit. Related Terms: 1) double-strand macromolecule (http://doi.org/10.1351/goldbook.D01851). 2) constitutional unit (http://doi.org/10.1351/goldbook.C01288). 3) sequence (http://doi.org/10.1351/goldbook.ST06775). Source: PAC, 1996, 68, 2287. 'Glossary of basic terms in polymer science (IUPAC Recommendations 1996)' on page 2295 (https://doi.org/10.1351/pac199668122287) Citation: 'ladder macromolecule' 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.L03441 License: The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms. Disclaimer: The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.