ASTm D2137-05

Designation:D2137–05StandardTestMethodsforRubberProperty—BrittlenessPointofFlexiblePolymersandCoatedFabrics1ThisstandardisissuedunderthefixeddesignationD2137;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheDepartmentofDefense.1.Scope1.1Thesetestmethodscoverthedeterminationofthelowesttemperatureatwhichrubbervulcanizatesandrubber-coatedfabricswillnotexhibitfracturesorcoatingcrackswhensubjectedtospecifiedimpactconditions.1.2ThevaluesstatedinSIunitsaretoberegardedasthestandard.Thevaluesgiveninparenthesesareforinformationonly.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2D751TestMethodsforCoatedFabricsD832PracticeforRubberConditioningforLow-TemperatureTestingD4483PracticeforDeterminingPrecisionforTestMethodStandardsintheRubberandCarbonBlackIndustries3.SummaryofTestMethods3.1Aspecifiednumberofspecimensisgivenasingle-impactunderspecifiedimpactandtemperatureconditionsuntilthetemperatureisfoundatwhichnofailuresoccur.Thisisdefinedasthebrittlenesstemperature.3.2Therearetwotestmethods:3.2.1TestMethodA—Coversthedeterminationofthelowesttemperatureatwhichrubbervulcanizateswillnotfractureorcrack.3.2.2TestMethodB—Coversthedeterminationofthelowesttemperatureatwhichrubber-coatedfabricswillnotfractureorexhibitcoatingcracks.3.3Thetestcanbedoneeitherinaliquidheattransfermediaorinagaseousmedia.4.SignificanceandUse4.1Thesetestmethodscovertheevaluationofrubbermaterialsorfabricscoatedtherewithsubjectedtolow-temperatureflexwithanimpactunderwell-definedconditionsofstrikerspeed.Theresponseislargelydependentoneffectsoflowtemperaturessuchascrystallization,incompatibilityofplasticizer,ortheinherentdynamicbehaviorofthematerialitself.Dataobtainedbythesetestmethodsmaybeusedtopredicttheproductbehaviorinapplicationswherethecondi-tionsaresimilartothosespecifiedinthesetestmethods.4.2Thesetestmethodshavebeenfoundusefulforspecifi-cationanddevelopmentpurposesbutdonotnecessarilyindicatethelowesttemperatureatwhichthematerialmaybeused.5.Apparatus5.1SpecimenClamp,designedsoastoholdfirmlythespecimen(s)ascantileverbeams(Fig.1).5.2Striker—Theedgeofthestrikershallhavearadiusof1.660.1mm(0.06360.005in.).Theedgeshallmoverelativetothespecimenatarectilinearspeedof2.060.2m/s(6.660.6ft/s)atimpactandimmediatelyafter.Thespeedofthesolenoid-activatedstrikershouldbefrequentlycalibratedbythemethoddescribedintheannex.Othertypesoftestersshallbecalibratedaccordingtotheirappropriatemethods.Inordertohavetherequiredspeed,caremustbetakentoensurethatthestrikingenergyofatleast3.0Jperspecimenisused.NOTE1—Thestrikermaybemotor-driven,solenoid-operated,gravity-activatedorspring-loaded.Themotor-driventestershouldbeequippedwithasafetyinterlocktopreventstrikermotionwhenthecoverisopen.1ThesetestmethodsareunderthejurisdictionofASTMCommitteeD11onRubberandarethedirectresponsibilityofSubcommitteeD11.14onTimeandTemperature-DependentPhysicalProperties.CurrenteditionapprovedOct.1,2005.PublishedOctober2005.Originallyapprovedin1962.Lastpreviouseditionapprovedin2000asD2137–94(2000).2ForreferencedASTMstandards,visittheASTMwebsite,@astm.org.ForAnnualBookofASTMStandardsvolumeinformation,refertothestandard’sDocumentSummarypageontheASTMwebsite.1Copyright©ASTMInternational,100BarrHarborDrive,POBoxC700,WestConshohocken,PA19428-2959,UnitedStates.5.2.1PositionofStrikingEdge—Thedistancebetweenthecenterlineofthestrikingedgeandtheclampsshallbe8.060.3mm(0.3160.01in.).Theclearancebetweenthestrikingarmandtheclampatandimmediatelyfollowingimpactshallbe:5.2.1.1TestMethodA—6.460.3mm(0.2560.01in.)5.2.1.2TestMethodB—Listedasfollows:SpecimenThickness,mm(in.)Clearance,mm(in.)1.65to2.20(0.065to0.087)6.460.3(0.2560.01)1.05to1.64(0.041to0.064)5.760.3(0.2260.01)0.55to1.04(0.022to0.040)5.260.3(0.2060.01)0.10to0.54(0.004to0.021)4.860.3(0.1960.01)NOTE2—ThedimensionalrequirementsforTestMethodBmaybeobtainedbyfabricatingindividualplatestofitthespecimenholderillustratedinFig.1.5.3TankorTestChamber—Atankforliquidheattransfermediaoratestchamberforgaseousmediaisrequired.Toensurethoroughcirculationoftheheattransfermedium,astirrershouldbeprovidedforliquidsandafanorblowerforgaseousmedia.5.4HeatTransferMedia:5.4.1LiquidHeatTransferMedium—Methanolistherec-ommendedheattransfermedium.Sincemethanolisflammableandtoxic,thebathshouldbeisolatedinaclosedhood.NOTE3—Anyotherliquidheattransfermediumthatremainsfluidatthetesttemperatureandwillnotappreciablyaffectthematerialtestedmaybeused.Thefollowingmaterialshavebeenuseddowntotheindicatedtemperatures.DowCorning—200fluids:°C5mm2/sviscosity−602mm2/sviscosity−76Methanol−90PropylAlcohol