【国外标准】 Standard Test Method for Rubber Chemicals—Diphenyl Guanidine (DPG) and Di-o-tolyl-guanidine (DOTG) Assay (Withdrawn 2018)

4.1 DPG and DOTG are used for rubber and latex vulcanization acceleration. The amount of DPG or DOTG may be of importance in predicting performance in rubber compounds and for raw material purchase and control.4.2 This test method may be used as a quality control tool and for research and development work.1.1 This test method covers the determination of assay of diphenyl guanidine (DPG) and di-o-tolyl-guanidine (DOTG). It is based on a visual titration of DPG or DOTG with hydrochloric acid (HCl).1.2 The assay is determined as mass percent.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 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.