Home

ISO 2871-2:1990
Subscribe to updates

Surface active agents -- Detergents -- Determination of cationic-active matter content -- Part 2: Cationic-active matter of low molecular mass (between 200 and 500)

This standard has been revised by: ISO 2871-2:2010

Abstract

The method is also suitable for other cationic-active materials. Not applicable if anionic and/or amphoteric surface active agents are present. The sample is titrated in a two-phase (aqueous chloroform) system against a standard anionic surface active agent in the presence of an indicator consisting of mixed anionic and cationic dyes. The cationic surface active agent present in the sample initially reacts with the anionic dye to form a salt which dissolves in the chloroform, imparting a blue colour to this layer. During the titration, the anionic surface active agent displaces the anionic dye and, at the end point, forms a salt with the cationic dye, imparting a greyish-pink colour to the chloroform layer.

 

Related standards

Got a question?

Check out our FAQs

Email customer services
or call us on +41 22 749 08 88
09:00 – 12:30, 14:00 – 17:00 (UTC+1).