ISO 2440:2019 pdf download

ISO 2440:2019 pdf download.Flexible and rigid cellular polymeric materials — Accelerated ageing tests
1 Scope
This document specifies, for flexible and rigid cellular polymeric materials, laboratory procedures which are intended to imitate the effects of naturally occurring reactions such as oxidation or hydrolysis by humidity. The physical properties of interest are measured before and after the application of the specified treatments. Test conditions are only given for open cellular latex, both open- and closed-cell polyurethane foams, and closed-cell polyolefin foams. Conditions for other materials will be added as required. The effect of the ageing procedures on any of the physical properties of the material can be examined, but those normally tested are either the elongation and tensile properties, or the compression or indentation hardness properties. These tests do not necessarily correlate either with service behaviour or with ageing by exposure to light. If desired, the ageing conditions contained in this document can be applied to composite structures containing any of the above types of cellular material. This can be helpful in the investigation of possible interactions between cellular materials and other substrates. Composite constructions can be in the form of complete finished products or representative small specimens cut there-from
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 23529, Rubber — General procedures for preparing and conditioning test pieces for physical test methods
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https: //www .iso .org/obp
— IEC Electropedia: available at http: //www .electropedia .org/
4 Apparatus
4.1 For dry heat ageing
4.1.1 Oven, with forced circulation, capable of maintaining the required temperature to within ± 3 °C.
It is recommended that a device be used to record the temperature, preferably continuously.
4.2 For humidity ageing
4.2.1 Ageing apparatus, of such a size that the total volume of the test pieces does not exceed 10 % of the free air space, and such that the test pieces are free of strain, freely exposed to the ageing atmosphere on all sides and not exposed to light.
4.2.2 Steam autoclave or similar vessel, capable of maintaining the required temperature to within ± 3 °C and of withstanding absolute pressures up to 300 kPa.
4.2.3 Glass vessel, with a suitable closure, and a water-bath or drying oven for heating the vessel,capable of maintaining the required temperature to within ± 3 °C.
4.3 For physical –property measurements
Use apparatus appropriate to the measurements of the physical property to be examined.