Term: intrinsic viscosity
https://doi.org/10.1351/goldbook.I03140

Definition:
The limiting value of the reduced viscosity, ηi/c or the inherent viscosity, ηinh, at infinite dilution of the polymer, i.e. \[[\eta] = \lim _{c\rightarrow 0}\frac{\eta _{\text{i}}}{c}=\lim _{c\rightarrow 0}\eta _{\text{inh}}\]

Notes:
0) This term is also known in the literature as the Staudinger index.
1) The unit must be specified; cm3 g-1 is recommended.
2) This quantity is neither a @V06627@ nor a pure number. The term is to be looked on as a traditional name. Any replacement by consistent terminology would produce unnecessary confusion in the polymer literature. Synonymous with limiting viscosity number.

Related Terms:
1) viscosity (http://doi.org/10.1351/goldbook.V06627).
2) reduced viscosity (<em>of a polymer</em>) (http://doi.org/10.1351/goldbook.R05220).
3) inherent viscosity (<em>of a polymer</em>) (<em>of a polymer</em>) (http://doi.org/10.1351/goldbook.I03033).

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

Citation: 'intrinsic viscosity' 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.I03140

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