Term: macromolecular isomorphism
https://doi.org/10.1351/goldbook.M03666

Definition:
Statistical co-crystallization of different constitutional repeating units which may either belong to the same copolymer chains (copolymer isomorphism) or originate from different homopolymer chains (homopolymer isomorphism). Isomorphism is a general term: in the strict sense, the crystal structure is essentially the same throughout the range of compositions; in isodimorphism or isopolymorphism, there are two or more crystal structures, respectively, depending on composition.

Related Terms:
1) crystallization (http://doi.org/10.1351/goldbook.C01434).
2) copolymer (<em>in polymers</em>) (http://doi.org/10.1351/goldbook.C01335).
3) homopolymer (<em>in polymers</em>) (http://doi.org/10.1351/goldbook.H02854).
4) constitutional repeating units (<em>in polymers</em>) (http://doi.org/10.1351/goldbook.C01286).

Source: Purple Book, 1st ed., p. 80 (http://old.iupac.org/publications/books/author/metanomski.html)

Citation: 'macromolecular isomorphism' 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.M03666

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