ASTM D 5629 - 05 Standard Test Method for Polyurethane Raw Materials: Determination of Acidity in Low-Acidity Aromatic Isocyanates and Polyurethane Prepolymers

American Society for Testing and Materials (ASTM). Current edition approved March 1, 2005. Published March 2005. Originally approved in 1994. Last previous edition approved in 1999 as D 5629 - 99. 3 p. This test method measures the acidity, expressed as ppm of hydrochloric acid (HCl), in aromatic isocyanate or polyurethane prepolymer samples of below 100 ppm acidity. The test method is applicable to products derived from toluene diisocyanate and methylene-bis-(4-phenylisocyanate) (see Note 1). Refer to Test Method D 6099 for determination of acidity in moderate- to high-acidity aromatic isocyanates.