Designation:D5666−95(Reapproved2019)StandardTestMethodforRubberChemicalAntidegradants—Purityofp-Phenylenediamine(PPD)AntidegradantsbyHighPerformanceLiquidChromatography1ThisstandardisissuedunderthefixeddesignationD5666;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1ThistestmethodcoversthepurityofTypeI,II,andIIIp-phenylenediamine(PPD)antidegradantsasdescribedinClassificationD4676byhighperformanceliquidchromatog-raphy(HPLC)usingultravioletdetectionandexternalstandardcalculations.1.2ExpertiseinHPLCisnecessarytothesuccessfulappli-cationofthistestmethod.1.3ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafety,health,andenvironmentalpracticesanddeter-minetheapplicabilityofregulatorylimitationspriortouse.1.5Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.2.ReferencedDocuments2.1ASTMStandards:2D3853TerminologyRelatingtoRubberandRubberLatices—AbbreviationsforChemicalsUsedinCom-poundingD4483PracticeforEvaluatingPrecisionforTestMethodStandardsintheRubberandCarbonBlackManufacturingIndustriesD4676ClassificationforRubberCompoundingMaterials—Antidegradants2.2ISOStandards:3ISO5725PrecisionofTestMethodsISO6472RubberCompoundingIngredients—Abbreviations3.Terminology3.1Definitions:3.1.1externalstandardcalculation—amethodofcalculat-ingthepercentcompositionbymeasuringtheareaoftheanalytepeak,multiplyingbyaresponsefactor,anddividi...
