ISO 1628-1:2021 Plastics — Determination of the viscosity of polymers in dilute solution using capillary viscometers — Part 1: General principles.
I Scope
This document defines the general conditions for the determination of the reduced viscosity, intrinsic viscosity and K-value of organic polymers in dilute solution. It defines the standard parameters that are applied to viscosity measurement.
This document is used to develop standards for measuring the viscosities in solution of individual types of polymer. It is also used to measure and report the viscosities of polymers in solution for which no separate standards exist.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 3105, Glass capillary kinematic viscometers — Spec qications and operating instructions
ISO 80000-1, Quantities and units — Part 1: General
ISO 80000-4, Quantities and units — Part 4: Mechanics
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 80000-1, ISO 80000-4 and the
following apply.
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— IEC Electropedia: available at
ISO 1628-1 pdf download.