BS 2782-1:Method 130A:1991
Methods of testing plastics. Thermal properties Determination of the thermal stability of polyvinyl chloride by the Congo red method
Standard number: | BS 2782-1:Method 130A:1991 |
Pages: | 10 |
Released: | 1991-04-30 |
ISBN: | 0 580 19593 7 |
Status: | Standard |
BS 2782-1:Method 130A:1991
This standard BS 2782-1:Method 130A:1991 Methods of testing plastics. Thermal properties is classified in these ICS categories:
- 83.080.20 Thermoplastic materials
1.1 This part of ISO 182 specifies a method for the determination of the thermal stability at elevated temperature of compounds and products based on vinyl chloride homopolymers and copolymers (in the following text abbreviated to PVC) which undergo dehydrochlorination (the evolution of hydrogen chloride).
1.2 The method is intended primarily as a simple and rapid quality-control test during the manufacture and conversion of PVC compounds. It may be used also for the characterization of PVC compounds and products.
It is suitable for coloured compounds and products where a discolouration test under the action of heat may be unsatisfactory.
1.3 The method is recommended for compounded materials and products only. It is not recommended for compounds in the form of dry blends since such materials may not be sufficiently homogeneous.
PVC compounds and products may evolve decomposition products in addition to hydrogen chloride at elevated temperatures. A limited number of these decomposition products may affect the time to colour change of the indicator paper. It is not possible to compensate for this effect within the scope of this part of ISO 182, and therefore care is necessary in comparing results for dissimilar compounds and products.
A test piece is maintained at a constant temperature and the amount of acidic gas evolved is measured using indicator paper.