ISO 2871-1:1988

An aliquot portion of a standard solution of sodium lauryl sulfate is titrated with a solution of the test sample, according to the direct two-phase titration procedure describes in ISO 2271. The method is applicable to solids or to aqueous solutions of the active material. The relative molecular mass of the cationic-active matter shall be known or previously determined if its content is expressed as a percentage by mass. The method is not applicable if anionic surface-active agents are present.