Designation:D3452−06(Reapproved2012)StandardPracticeforRubber—IdentificationbyPyrolysis-GasChromatography1ThisstandardisissuedunderthefixeddesignationD3452;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheDepartmentofDefense.PART1.IDENTIFICATIONOFSINGLEPOLYMERS1.Scope1.1Thispracticecoverstheidentificationofpolymersinrawrubbers,andcuredanduncuredcompounds,basedonasinglepolymer,bythegaschromatographicpatternsoftheirpyrolysisproducts(pyrograms).Implementationofthisguidepresupposesaworkingknowledgeoftheprinciplesandtech-niquesofgaschromatography,sufficienttocarryoutthispracticeandtointerprettheresultscorrectly.21.2Thispracticewillidentifythefollowingpolymers:1.2.1Polyisopreneofnaturalorsyntheticorigin,1.2.2Butadiene-styrenecopolymers,1.2.3Polybutadiene,1.2.4Polychloroprene,1.2.5Butadiene-acrylonitrilecopolymers,1.2.6Ethylene-propylenecopolymersandrelatedterpolymers,and1.2.7Isobutene-isoprenecopolymers.1.3Thispracticewillnotdifferentiatethefollowingpoly-mers:1.3.1Naturalpolyisoprenefromsyntheticpolyisoprene.1.3.2Butadiene-styrenecopolymersproducedbysolutionandemulsionpolymerization.Itissometimespossibletodistinguishbutadiene-styrenecopolymerscontainingdifferentamountsofstyreneaswellasrandompolymersfromblockpolymers.1.3.3Polybutadienewithdifferentmicrostructures.1.3.4Differenttypesofpolychloroprenes.1.3.5Butadiene-acrylonitrilecopolymerswithdifferentmonomerratios.1.3.6Ethylene-propylenecopolymerswithdifferentmono-merratios,aswellasthecopolymersfromtherelatedterpoly-mers.1.3.7Isobutene-isoprenecopolymers(butylrubbers)fromhalogenatedbutylrubbers.1.3.8Polyisoprenecontainingdifferentamountsofcis-transisomers.1.3.9Thepracticedoesnotidentifyeboniteorhardrubbers.1.4ThevaluesstatedinSIunitsaretoberegardedasstandard.Thevalue...
