Designation:D8036−16StandardTestMethodforPolyurethaneRawMaterials:DeterminationofDimerRatioinPureMDI1ThisstandardisissuedunderthefixeddesignationD8036;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethoddeterminestheratiooftheinfraredabsorbanceofuretidinedione(dimer)inmethylene-4,4’-di-(phenylisocyanate)toaninfraredabsorbanceatareferencewavelengthwithinthesamematerial.Itisapplicabletomonomericmethylene-di(phenylisocyanate),or“PureMDI,”containing95%orgreatermethylene-4,4’-di(phenylisocyanate).1.2Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.NOTE1—ThereisnoknownISOequivalenttothisstandard.2.ReferencedDocuments2.1ASTMStandards:2D883TerminologyRelatingtoPlasticsE691PracticeforConductinganInterlaboratoryStudytoDeterminethePrecisionofaTestMethod3.Terminology3.1TerminologyinthistestmethodisinaccordancewithTerminologyD883.3.2DefinitionsofTermsSpecifictoThisStandard:3.2.1dimer,n—uretidinedione,withthestructureinFig.1,isanundesirablereactionproductoftwoormoreisocyanategroups.4.SummaryofTestMethod4.1Theinfraredspectrumofadichloromethanesolutionofthesampleisrecordedinthe1600to2000cm–1region.Theabsorbanceratioofthepeakmaximumatapproximately1778cm–1,correspondingtothecarbonylspresentinuretidinedione,tothepara-substitutedringcombinationpeakmaximumatapproximately1900cm–1iscalculated.5.SignificanceandUse5.1ThistestmethodcanbeusedforresearchorforqualitycontroltodeterminethedimerratioofPureMDI.5.2UretidinedionebeginsforminginPureMDIwiththerateofformationincreasingwithincreasingtemperature.HighlevelscanaffecttheappearanceofPureMDIandthequalityofproductsmadefr...
