ISO 1183-2:2019 Plastics一Methods for determining the density of non-cellular plastics – Part 2: Density gradient column method.
This document specifies a gradient column method for the determination of the density of non-cellular moulded or extruded plastics or pellets in void-free form. Density gradient columns are columns containing a mixture of two liquids, the density in the column increasing uniformly from top to bottom.
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. The density of plastic materials can 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.
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 291, Plastics — Standard atmospheres for conditioning and testing
ISO 1183-1, Plastics — Methods for determining the density of non-cellular plastics — Part 1: Immersion
method, liquid pycnometer method and titration method
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/ohp
— fEC Electropedia: available at http://www.electropedia.org/
3.1
density
ratio of the mass m of a sample to its volume V (at the temperature T) expressed in kg/m3, kg/dm3 (g/ cm3), or kg/I (g/ml)
Note 1 to entry: The following terms, based upon ISO 80000-4111, are given in Table 1 for clarification.
4 Conditioning
Conditioning and testing shall be in accordance with ISO 291 or the appropriate material standard. In general, conditioning specimens to constant temperature is not required, because the determination itself brings the specimen to the constant temperature of the test.
Specimens which change in density during the test to such an extent that the change is greater than the required accuracy of the density determination shall be conditioned prior to measurement in accordance with the applicable material specification. When changes in density with time or atmospheric conditions are the primary purpose of the measurements, the specimens shall be conditioned as described in the material specification and, if no material specification exists, then as agreed upon by the interested parties.ISO 1183-2 pdf download.