【国外标准】 Standard Test Method for Synthetic Quaternary Ammonium Salts in Fabric Softeners by Potentiometric Titrations (Withdrawn 2023)

4.1 This test method is used to determine the quaternary ammonium salts commonly found in fabric softeners. Quaternary ammonium compounds being the active ingredients in fabric softeners requires accurate determination to assess the cost and performance of such compounds.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. 2.1.3 The analytical procedure appears in the following order:  SectionApparatus  5Reagents  6Preparation of standard reagents  7Standardization of hyamine solution  9Safety precautions  8Procedure for determination of dialkyl dimethyl quaternaries 10Procedure for determination of diamidoamine based quaternaries 111.4 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.