This part of GB/T 12009 specifies two methods for the determination of isocyanate content in aromatic isocyanates for polyurethane production. Method A of this part is applicable to refined toluene diisocyanate (hereinafter referred to as TDI), diphenylmethane diisocyanate (hereinafter referred to as MDI), polymethylene polyphenylisocyanate (hereinafter referred to as polymeric MDI) and their prepolymers; Method B applies to refined, crude or modified isocyanates derived from TDI, MDI and polymeric MDI, and also to mixtures of TDI, MDI and polymeric MDI isomers. Other isocyanates, if proven suitable, can also be used by this method. This section does not apply to blocked isocyanates.
GB/T 12009.4-2016 Referenced Document
GB/T 12009.5 Aromatic isocyanates for plastic polyurethane production Part 5: Determination of acidity Amendment No. 1
GB/T 601-2002 Chemical reagent Preparations of standard volumetric solutions
GB/T 6682 Water for analytical laboratory use.Specification and test methods
GB/T 12009.4-2016 history
0000 GB/T 12009.4-2016(XG1-2019)
2020GB/T 12009.4-2016 Plastics.Aromatic isocyanates for use in the production of polyurethane.Part 4:Determination of isocyanate content
1989GB/T 12009.4-1989 Polymethylene polyphenyl isocyanate--Determination of isocyanato content