Designation:D4550–98StandardClassificationforThermoplasticElastomer-Ether-Ester(TEEE)1ThisstandardisissuedunderthefixeddesignationD4550;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheDepartmentofDefense.INTRODUCTIONThisclassificationisintendedtobeameansofcallingoutmaterialsusedinthefabricationofenditemsorparts.Itisnotintendedfortheselectionofmaterials.Materialselectionshouldbemadebythosehavingexpertiseintheplasticsfieldaftercarefulconsiderationofthedesignandtheperformancerequiredofthepart,theenvironmenttowhichitwillbeexposed,thefabricationprocesstobeemployed,theinherentpropertiesofthematerialotherthanthosecoveredbythisspecification,andtheeconomics.1.Scope1.1Thisclassificationcoverssegmentedblockcopolyether-esterelastomerssuitableformoldingandextrusion.Thisclassificationallowsfortheuseofsegmentedblockcopolyether-esterelastomersthatarerecycled,reconstituted,recycled-regrind,recovered,orreprocessed,oracombinationthereof,providedthattherequirementsasstatedinthisclassificationaremet.Itistheresponsibilityofthesupplierandthebuyerofrecycled,reconstituted,recycled-regrind,recov-ered,orreprocessed,oracombinationthereof,copolyether-esterelastomerstoensurecompliance(seeGuideD5033).1.2Thepropertiesincludedinthisclassificationarethoserequiredtoidentifythecompositionscovered.Theremaybeotherrequirementsnecessarytoidentifyparticularcharacter-isticsimportanttospecializedapplications.ThesemaybespecifiedusingthesuffixesasgiveninSection5.1.3Thisclassificationsystemandsubsequentlinecallout(specification)areintendedtoprovideameansofcallingoutplasticmaterialsusedinthefabricationofenditemsorparts.Itisnotintendedfortheselectionofmaterials.Materialselectionshouldbemadebythosehavingexpertiseintheplasticfieldaftercarefulconsiderationofthe...
