Designation:D4338−97(Reapproved2021)StandardTestMethodforFlexibilityDeterminationofSupportedAdhesiveFilmsbyMandrelBend1ThisstandardisissuedunderthefixeddesignationD4338;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheU.S.DepartmentofDefense.1.Scope1.1Thistestmethodcoversthedeterminationoftheflex-ibilityofanadhesivefilmbondedtoaflexiblesubstrate.Theresultsareusefulforcomparingflexibilityofadhesivesandnotforabsolutecharacterizationofadhesives.1.2ThevaluesstatedinSIunitsaretoberegardedasthestandard.Thevaluesgiveninparenthesesareprovidedforinformationpurposesonly.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafety,health,andenvironmentalpracticesanddeter-minetheapplicabilityofregulatorylimitationspriortouse.1.4Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.2.ReferencedDocuments2.1ASTMStandards:2D609PracticeforPreparationofCold-RolledSteelPanelsforTestingPaint,Varnish,ConversionCoatings,andRelatedCoatingProductsD907TerminologyofAdhesivesD3111PracticeforFlexibilityDeterminationofHot-MeltAdhesivesbyMandrelBendTestE171PracticeforConditioningandTestingFlexibleBarrierPackaging3.Terminology3.1Definitions—Fortermsusedinthisstandard,refertoTerminologyD907.3.2DefinitionsofTermsSpecifictoThisStandard:3.2.1mandrel,n—cylindricalrod.4.SummaryofTestMethod4.1Atestsubstratecoatedwithafilmofadhesive,properlysizedandconditioned,isfoldedtoformaninvertedU-shapedangleoverthemandrelmaintainingint...
