Plastics — Phenol-formaldehyde mouldings — Determination of free ammonia and ammonium compounds — Colorimetric comparison method
NORMA vydaná dňa 1.10.1977
Designation standards: ISO 120:1977
Publication date standards: 1.10.1977
The number of pages: 2
Approximate weight : 6 g (0.01 lbs)
Country: International technical standard
Kategória: Technické normy ISO
Description / Abstract: Specification of a semi-quantitative method. The content of free ammonia in a moulded article is of importance, when corrosion of metal inserts or contamination in contact with the article has to be considered. Distillation of the aqueous extract from a powdered test portion, coloration of the distillate by reaction with Nessler reagent and comparison of the colour with that of standard matching solutions.