1.1 This test method covers the purity of Type I, II, and III p-phenylenediamine (PPD) antidegradants as described in Classification D 4676 by high performance liquid chromatography (HPLC) using ultraviolet detection and external standard calculations.

1.2 Expertise in HPLC is necessary to the successful application of this test method.

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.