Term: relative viscosity increment
https://doi.org/10.1351/goldbook.R05283

Definition:
The ratio of the difference between the viscosities of solution and solvent to the viscosity of the solvent, i.e. η i = η- η s η s, where η is the viscosity of the solution and η s is the viscosity of the solvent. The use of the term 'specific viscosity' for this quantity is discouraged, since the relative viscosity increment does not have the attributes of a specific quantity.

Related Terms:
1) viscosity (http://doi.org/10.1351/goldbook.V06627).
2) relative viscosity (http://doi.org/10.1351/goldbook.R05282).

Source: Purple Book, 1st ed., p. 63 (http://old.iupac.org/publications/books/author/metanomski.html)

Citation: 'relative viscosity increment' 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.R05283

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