Designation:D5044−06(Reapproved2017)StandardTestMethodforRubberCompoundingMaterials—Free2-Mercaptobenzothiazole(MBT)inBenzothiazylDisulfide(MBTS)1ThisstandardisissuedunderthefixeddesignationD5044;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodcoverstheprocedureforestimationoftheacidicimpuritiesinbenzothiazyldisulfide(MBTS).1.2ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.1.4Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.2.ReferencedDocuments2.1ASTMStandards:2D1193SpecificationforReagentWaterD4483PracticeforEvaluatingPrecisionforTestMethodStandardsintheRubberandCarbonBlackManufacturingIndustries3.SummaryofTestMethod3.1AsampleofMBTSisdissolvedinsolvent.Afteradditionofanacetatebuffer,water,andstarchsolution,thesolutionistitratedwithiodine.3.2MBTSissparinglysolubleinanyorganicsolvent.MBT,majorimpurityinMBTS,isverysoluble.StirringthereforewilldissolveMBT,MBTScouldstayundissolved.4.SignificanceandUse4.12-Mercaptobenzothiazole(MBT)isusuallythemajorimpurityinMBTS.FreeMBTmaybedeterminedbythistestmethod.4.2MBTandMBTSareusedforrubberandlatexvulcani-zationacceleration.TheamountofMBTinMBTSmaybeofimportanceinpredictingperformanceinrubbercompoundsandforrawmaterialpurchaseandcontrol.4.3Thistestmethodmaybeusedasaqualitycontrol...
