ISO 1183-1:2025

This document specifies three methods for the determination of the density of non-cellular plastics in the form of void-free moulded or extruded objects, as well as powders, flakes and granules.
—     Method A: Immersion method, for solid plastics (except for powders) in void-free form.
—     Method B: Liquid pycnometer method, for particles, powders, flakes, granules or small pieces of finished parts.
—     Method C: Titration method, for plastics in any void-free form.
NOTE            Density is frequently used to follow variations in physical structure or composition of plastic materials. Density can also be useful in assessing the uniformity of samples or specimens. Often, the density of plastic materials depend upon the choice of specimen preparation method. When this is the case, precise details of the specimen preparation method are intended to be included in the appropriate material specification. This note is applicable to all three methods.
Annex C provides further information for calculating the volume of the specimen used for the determination of the density in the case that method A (the immersion method) is applied.