ISO 14898:1999 PDF

Scope: This International Standard specifies methods for the measurement of the acidity of aromatic isocyanates and prepolymers used as polyurethane raw materials. Method A is a straightforward titration without a blank and is primarily applicable to products derived from crude or modified methylene-bis-(4-phenylisocyanate), polymethylene polyphenylisocyanates and toluene diisocyanate having moderate to high (> 100 μg/g ) levels of acidity. Method B is applicable to refined, crude or modified isocyanates derived from methylene-bis-(4-phenylisocyanate), polymethylene polyphenylisocyanate and toluene diisocyanate having low (< 100 μg/g ) levels of acidity, and a blank is employed. These methods can also be used for isomeric mixtures of toluene diisocyanate, methylene-bis-(4-phenylisocyanate) and polymethylene polyphenylisocyanate. Other aromatic isocyanates may be analysed by this method if precautions are taken to verify suitability.

ISO 14898:1999 Referenced Document

ISO 3696:1987 Water for analytical laboratory use; Specification and test methods
ISO 4787:1984 Laboratory glassware; Volumetric glassware; Methods for use and testing of capacity
ISO 4788:1980 Laboratory glassware; Graduated measuring cylinders
ISO 6353-1:1982 Reagents for chemical analysis; Part 1 : General test methods
ISO 6353-2:1983 Reagents for chemical analysis; Part 2 : Specifications; First series
ISO 6353-3:1987 Reagents for chemical analysis; Part 3 : Specifications; Second series
ISO 648:1977 Laboratory glassware; One-mark pipettes

2011 ISO 14898:1999/Amd 1:2011 Plastics - Aromatic isocyanates for use in the production of polyurethane - Determination of acidity; Amendment 1
1999 ISO 14898:1999 Plastics - Aromatic isocyanates for use in the production of polyurethane - Determination of acidity