Title: ideal binary copolymerisation
Long Title: IUPAC Gold Book - ideal binary copolymerisation
DOI: 10.1351/goldbook.15405
Status: current

Definition
Binary copolymerization in which the relative rates of incorporation of the two types of monomer into the copolymer are independent of the nature of the monomer unit at the end of a propagating chain.

Notes
1) In an ideal binary copolymerization, \(k_{11}/k_{21} = k_{12}/k_{22}\) and \(r_{12} r_{21} = 1\). See monomer reactivity ratios.
2) In the special case of an ideal binary copolymerization in which \(r_{12} = r_{21} = 1\), the two monomers show equal reactivities toward both types of propagating species. Thus, \(k_{11} = k_{21}\) and \(k_{12} = k_{22}\). Hence, copolymerization of a mixture of two monomers with any ratio of monomer concentrations in the monomer feed gives rise to a copolymer in which the molar ratio of monomer units is identical to that in the monomer feed. (See also azeotropic copolymerization.)

Related Terms
- Binary copolymerization: https://goldbook.iupac.org//terms/view/15383
- azeotropic copolymerization: https://goldbook.iupac.org//terms/view/15381
- monomer reactivity ratios: https://goldbook.iupac.org//terms/view/15410

Source
- PAC, 2008, 80, 2163. 'Glossary of terms related to kinetics, thermodynamics, and mechanisms of polymerization (IUPAC Recommendations 2008)' on page 2176 (https://doi.org/10.1351/pac200880102163)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/15405/html
- json: https://goldbook.iupac.org/terms/view/15405/json
- xml: https://goldbook.iupac.org/terms/view/15405/xml

Citation: Citation: 'ideal binary copolymerisation' 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.15405
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Accessed: 2026-06-28T22:47:55+00:00