ISO 6796:1981
Polyglycols for industrial use; Determination of hydroxyl number; Phthalic anhydride esterification method

Standard No.

ISO 6796:1981

Release Date

1981

Published By

International Organization for Standardization (ISO)

Latest

ISO 6796:1981

Scope

The hydroxy groups present in a test portion are esterified with phthalic anhydride. The excess phthalic anhydrids is hydrolyzed and the phthalic acid formed is neutralized with standard volumetric sodium hydroxide solution. If the sample contains free acidity or alkalinity a corresponding correction is made. From the corrected hydroxyl number, the apparat relative molecular mass may be calculated by a formula given.

ISO 6796:1981 history

• 1981 ISO 6796:1981 Polyglycols for industrial use; Determination of hydroxyl number; Phthalic anhydride esterification method