1.1 This test method describes a potentiometric titration procedure for the determination of quaternary ammonium salts in fabric softeners. This test method is intended for the analysis of known quaternary ammonium salts such as the dialkyl dimethyl quaternary ammonium compound type and the diamidoamine based quaternary ammonium compound type.

1.2 The quaternary ammonium salts conform to the structures shown in Fig. 1 and Fig. 2.

 
X⁻ = chloride or methyl sulfate
R = fatty alkyl groups saturated or unsaturated, normal or branched C₈  − C₂₂

FIG. 1 Dialkyl Dimethyl Quaternaries

 
X⁻ = usually methyl sulfate
R = fatty alkyl groups, saturated or unsaturated, normal or branched C ₁₂ − C₁₈
R₁ = 2-hydroxyethyl,
  2-hydroxypropyl

FIG. 2 Diamidoamine Based Quarternaries

1.3 The analytical procedure appears in the following order:

1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.5 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. See 6.4, 6.6, 6.7 and Section 8 for specific warning statements.