This part of GB/T 12009 specifies the method for the determination of acidity in aromatic isocyanate for polyurethane production by potentiometric titration. This section applies to the determination of the acidity of aromatic isocyanates and their prepolymers of polyurethane raw materials. Method A is suitable for crude or modified diphenylmethane diisocyanate, polymethylene polyphenylisocyanate and toluene diisocyanate products with medium/high acidity values (>100 μg/g). Method B is suitable for low acidity value (<100 μg/g) refined, crude or modified diphenylmethane diisocyanate, polymethylene polyphenylisocyanate and toluene diisocyanate. These methods are also applicable to mixtures of isomers of toluene diisocyanate, diphenylmethane diisocyanate and polymethylene polyphenylisocyanate. Other isocyanates can also be used in this way if it proves suitable.
GB/T 12009.5-2016 Referenced Document
GB/T 6682 Water for analytical laboratory use.Specification and test methods
GB/T 12009.5-2016 history
0000 GB/T 12009.5-2016(XG1-2019)
2020GB/T 12009.5-2016 Plastics.Aromatic isocyanates for use in the production of polyurethane.Part 5:Determination of acidity