ASTM D4273-99

1.1 Test Method A-Fluorine-19 Nuclear Magnetic Resonance Spectroscopy (fluorine-19 NMR), measures the primary hydroxyl content in ethylene oxide-propylene oxide polyethers used in flexible urethane foams. It is suitable for polyethers with hydroxyl numbers of 24 to 300 and primary hydroxyl percentages of 2 to 98.

1.2 Test Method B-Carbon-13 Nuclear Magnetic Resonance Spectroscopy (carbon-13 NMR), measures the primary hydroxyl content of ethylene-oxide-propylene oxide polyethers used in preparing flexible foams. It is suitable for polyethers with hydroxyl numbers of 24 to 109 and primary hydroxyl contents of 10 to 90% (see Note 1).

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.