Title: conformational melting
Long Title: IUPAC Gold Book - conformational melting
DOI: 10.1351/goldbook.12751
Status: current

Definition
Step-like increase in the conformational entropy of macromolecules, or parts of macromolecules.

Notes
1) This melting can be caused by a temperature change or by interaction with a solvent.
2) Conformational melting normally occurs along with crystalline melting in a partially crystalline polymer.

Example
A helix–coil transition is an example of conformational melting.

Related Term
- conformational entropy: https://goldbook.iupac.org//terms/view/12750

Source
- PAC, 2013, 85, 1017. 'Glossary of terms relating to thermal and thermomechanical properties of polymers (IUPAC Recommendations 2013)' on page 1022 (https://doi.org/10.1351/PAC-REC-12-03-02)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/12751/html
- json: https://goldbook.iupac.org/terms/view/12751/json
- xml: https://goldbook.iupac.org/terms/view/12751/xml

Citation: Citation: 'conformational melting' 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.12751
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Accessed: 2026-08-10T10:42:11+00:00