ASTMD345792=07595300535368269AMERICANSOCIETYFORTESTINGANDMATERIALS1916RaceStPhlladelphia,Pa19103ReprintedfromtheAnnwlBookofASTMStandards.CopyrightASTMifnotlistedInthecurrentwmblnedindex,willappearinthenextedfin.AnAmericanNalionalStandard#TbDesignation:D1457-92StandardSpecificationforPolytetrafluoroethylene(PTFE)MoldingandExtrusionMaterials'ThisstandardisissuedunderthefixeddesignaiionD1457;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision.theyearoflastrevision.Anumberinparenthesesindicatcstheyearoflastreapproval.Asuperscriptepsilon(0indicatesaneditorialchangesincethelastrevisionorreapproval.Thisstandardliasbeenapprovedforusebyagencieso]!heDepur~nieniofDejnsrIOrepluceL-P-403c.CunsiiltrlieDoDín(1e.rifSpecijicarionsandStandardsforthespecijicyearwhichhasbeenadoptedbytlieDeparlriierir($Definse.1.Scope1.1Thisspecificationcoversmoldingandextrusionresinsofpolytetrafluoroethylene(PTFE)thathaveneverbeenmeltedafterpreformingormoldingandarenormallyproccsscdbymethodssimilartothoseuscdinpowdermetallurgyorceramics,orbyramextrusionorextrusionwithavolatileaid.ThesePTFEresinsarehomopolymersoftetrafluoroethyleneorcopolymerscontainingnotmorethan1%byweightofotherfluoromonomers.Theusualmethodsofprocessingthermoplasticsgenerallyarenotapplicabletothesematerialsbecauseoftheirviscoelasticpropertiesatprocessingtemperatures.ThematerialsincludedhereindonotincludemixturesofPTFEresinwithadditivessuchascolorants,fillers,plasticizers,anyfabricatedarticles,orreprocessedorregroundresin.Themethodsandpropertiesincludedarethoserequiredtoidentifythevarioustypesofresins.AdditionalproceduresareprovidedinAppendixX1forfurthercharacterizationoftheresins.1.2ThevaluesstatedinSIunitsasdetailedinPracticeE380aretoberegardedasthestandard,andthepracticesofE380areincorporatedherein.1.3Thefollowingprecautionarycaveatpertainsonlytothetestmethodsportion,Section13,ofthisspecification:Thisstandarddoesnotpurporttoaddressallofthesafetyproblems,ifany,associatedwithitsuse.I...
