Term: main-chain scission
https://doi.org/10.1351/goldbook.MT07140

Definition:
Chemical reaction that results in the breaking of main-chain bonds of a polymer molecule.

Note: Some main-chain scissions are classified according to the mechanism of the scission process: hydrolytic, mechano-chemical, thermal, photo-chemical, or oxidative scission. Others are classified according to their location in the @B00574@ relative to a specific structural feature, for example, α-scission (a scission of the C–C bond alpha to the carbon atom of a photo-excited carbonyl group) and β-scission (a scission of the C–C bond beta to the carbon atom bearing a radical), etc.

Related Terms:
1) backbone (http://doi.org/10.1351/goldbook.B00574).
2) polymer molecule (http://doi.org/10.1351/goldbook.M03667).

Source: PAC, 2004, 76, 889. 'Definitions of terms relating to reactions of polymers and to functional polymeric materials (IUPAC Recommendations 2003)' on page 892 (https://doi.org/10.1351/pac200476040889)

Citation: 'main-chain scission' 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.MT07140

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