1、InternationalStandardISO23649IULTCSIUC444Firstedition2025-02ChemicalsfortheleathertanningindustryDeterminationofcyclosiloxanesProduitschimiquespourindustriedutannageducuir一DeterminationdescyclosiloxanesReferencenumbersISO23649:2025(en)IULTCS/IUC444:2025(en)COPYRIGHTPROTECTEDDOCUMENTISO2025Allrightsr
2、eserved.Unlessotherwisespecified,orrequiredinthecontextofitsimplementation,nopartofthispublicationmaybereproducedorutilizedotherwiseinanyformorbyanymeans,electronicormechanical,includingphotocopying,orpostingontheinternetoranintranet,withoutpriorwrittenpermission.PermissioncanberequestedfromeitherIS
3、OattheaddressbeloworISO,smemberbodyinthecountryoftherequester.ISOcopyrightofficeCP401Ch.deBlandonnet8CH-1214Vernier,GenevaPhone:+4122749Ol11Email:copyrightiso.orgWebsite:www.iso.orgPublishedinSwitzerlandContentsPageForewordivIntroductionv1 Scope12 Normativereferences13 Termsanddefinitions14 Principl
4、e15 Apparatus16 Reagents27 Samplingandsamplepreparation38 Procedure38.1 Samplesolutionpreparation38.2 Liquid-liquidextraction38.3 Instrumentalanalysis49 Expressionofresults410 Precision411 Testreport4Annex A (informative)ChromatographicanalysisoperatingparametersforGC-MS6Annex B (informative)Precisi
5、on:reliabilityofthemethod7Annex C (normative)Samplepreparationfornon-water-solublechemicals8Bibliography9ForewordISO(theInternationalOrganizationforStandardization)isaworldwidefederationofnationalstandardsbodies(ISOmemberbodies).TheworkofpreparingInternationalStandardsisnormallycarriedoutthroughISOt
6、echnicalcommittees.Eachmemberbodyinterestedinasubjectforwhichatechnicalcommitteehasbeenestablishedhastherighttoberepresentedonthatcommittee.Internationalorganizations,governmentalandnon-governmentatinliaisonwithISO,alsotakepartinthework.ISOcollaboratescloselywiththeInternationalElectrotechnicalCommi
7、ssion(IEC)onallmattersofelectrotechnicalstandardization.TheproceduresusedtodevelopthisdocumentandthoseintendedforitsfurthermaintenancearedescribedintheISO/IECDirectives,Part1.Inparticular,thedifferentapprovalcriterianeededforthedifferenttypesofISOdocumentsshouldbenoted.Thisdocumentwasdraftedinaccord
8、ancewiththeeditorialrulesoftheISO/IECDirectives,Part2(seeWWW.iso.org/directives).ISOdrawsattentiontothepossibilitythattheimplementationofthisdocumentmayinvolvetheuseof（八）patent(三).ISOtakesnopositionconcerningtheevidence,validityorapplicabilityofanyclaimedpatentrightsinrespectthereof.Asofthedateofpub
9、licationofthisdocument,ISOhadnotreceivednoticeof（八）patent(三)whichmayberequiredtoimplementthisdocument.However,implementersarecautionedthatthismaynotrepresentthelatestinformation,whichmaybeobtainedfromthepatentdatabaseavailableatWWW.iso.org/patents.ISOshallnotbeheldresponsibleforidentifyinganyorallsu
10、chpatentrights.Anytradenameusedinthisdocumentisinformationgivenfortheconvenienceofusersanddoesnotconstituteanendorsement.Foranexplanationofthevoluntarynatureofstandards,themeaningofISOspecifictermsandexpressionsrelatedtoconformityassessment,aswellasinformationaboutISO,sadherencetotheWorldTradeOrgani
11、zation(WTO)principlesintheTechnicalBarrierstoTrade(TBT),seeWWW.iso.org/iso/foreword.htmLIULTCS1originallyformedin1897,isaworld-wideorganizationofprofessionalleathersocietiestofurthertheadvancementofleatherscienceandtechnology.IULTCShasthreeCommissions,whichareresponsibleforestablishinginternationalm
12、ethodsforthesamplingandtestingofleather.ISOrecognizesIULTCSasaninternationalstandardizingbodyforthepreparationoftestmethodsforleather.ThisdocumentwaspreparedbytheChemicalTestCommissionoftheInternationalUnionofLeatherTechnologistsandChemistsSocieties(IUCCommission,IULTCS),incollaborationwiththeEurope
13、anCommitteeforStandardization(CEN)TechnicalCommitteeCEN/TC289,Leather,inaccordancewiththeAgreementontechnicalcooperationbetweenISOandCEN(ViennaAgreement).Anyfeedbackorquestionsonthisdocumentshouldbedirectedtotheusersnationalstandardsbody.AcompletelistingofthesebodiescanbefoundatWWW.iso.org/members.h
14、tml.IntroductionThisdocumentincludesaprocedureforanalysingcertaincyclosiloxanesusinggaschromatography(GC)withmassspectrometer(MS)equipment.WiththisanalyticalmethodOctamethylcyclotetrasiloxane(D4),decamethylcyclopentasiloxane(D5)anddodecamethylcyclohexasiloxane(D6)canbedetermined.Intheleatherindustry
15、cyclosiloxanes(D4),(D5and(D6)areusedinthemanufactureofsilicone-basedwaterproofingfatliquorsandcanalsobeusedintheproductionofsilicone-basedfinishingchemicalsespeciallyashandlemodifiers.Atpresent,theofficialclassificationrecognisedintheEUisthefollowing. Octamethylcyclotetrasiloxane(D4isclassifiedasper
16、sistent,bioaccumulativeandtoxic.t1l Decamethylcyclopentasiloxane(D5)isclassifiedaspersistent,bioaccumulativeandtoxic.H Dodecamethylcyclohexasiloxane(D6)isclassifiedaspersistent,bioaccumulativeandtoxic.BlInternationalStandardIS023649:2025(en)IULTCSIUC202S(en)ChemicalsfortheleathertanningindustryDeter
17、minationofcyclosiloxanes1ScopeThisdocumentspecifiesamethodfordeterminingthetotalcontentofthefollowingcyclosiloxanesinchemicalsfortheleathertanningindustry: Octamethylcyclotetrasiloxane(D4); decamethylcyclopentasiloxane(D5); dodecamethylcyclohexasiloxane(D6);Thismethodrequirestheuseofgaschromatograph
18、y(GC)equippedwithasinglequadrupolemassspectrometer(MS)toidentifyandquantifythecyclosiloxanes.2 NormativereferencesThefollowingdocumentsarereferredtointhetextinsuchawaythatsomeoralloftheircontentconstitutesrequirementsofthisdocument.Fordatedreferences,onlytheeditioncitedapplies.Forundatedreferences,t
19、helatesteditionofthereferenceddocument(includinganyamendments)applies.ISO3696,WaterforanalyticallaboratoryuseSpecificationandtestmethods3 TermsanddefinitionsNotermsanddefinitionsarelistedinthisdocument.ISOandIECmaintainterminologydatabasesforuseinstandardizationatthefollowingaddresses: ISOOnlinebrow
20、singplatform:availableathttps:WWW.iso.org/obp IECElectropedia:availableathttps:WWWeleCtrOPedia.org4 PrincipleAftersolubilizingthechemicalspecimeninwater,aliquid-liquidextractionwithahexane-ethylacetatemixtureisperformedandthenthecyclosiloxanesareanalysedbygas-chromatographywithsinglequadrupolemasssp
21、ectrometry(GC-MS).Usinganexternalcalibration,quantificationisperformedtakingintoaccounttherecoveryrateoftheinternalstandard.5 ApparatusTheusuallaboratoryapparatusand,inparticular,thefollowingshallbeused:5.1 Ultrasonicbath,capableofoperatingatastartingtemperatureof40to45.5.2 Horizontalshaker,capableo
22、fatleast300cyclesperminute.5.3 Glasscontainerwithascrewcap,e.g.volumeof20ml.IS023649:2025(en)IULTCSIUC444:2025(en)5.4 Suitablesyringemembranefilters,e.g.polyamidewithporesize0,2m.5.5 Volumetricflasks,e.g.volumeof10mland100ml.5.6 Plastictesttubes,50ml,orsuitablevesselthatallowsseparationoforganicanda
23、queousphase,thatcanbesealedforvigorousshaking.5.7 GCvials,withcap,e.g.volumeof2ml.5.8 Analyticalbalance,witharesolutionof1mgorbetter.5.9 Pipettes,varioussizes,e.g.volumeof0,1mlto10ml.5.10 Centrifuge,capableofatleast4000rmin.5.11 Instrumentalequipment,GC-MS.6 ReagentsIfnototherwisespecified,analytica
24、lreagentgradechemicalsshallbeused.6.1 n-hexane,CASRegistryNumber(CASRN)I)110-54-3lsuitableforGC-MSanalysis.6.2 Ethylacetate,CASRN141-78-6,suitableforGC-MSanalysis.6.3 Watergrade1,accordingtoISO3696.6.4 Sodiumchloride,CASRN7647-14-5,purity99,0%(massfraction).6.5 Magnesiumsulphateanhydrous,CASRN7487-8
25、8-9,purity99,0%(massfraction).6.6 Octamethylcyclotetrasiloxane(D4),CASRN556-67-2,purity99,0%(massfraction).6.7 Decamethylcyclopentasiloxane(D5),CASRN541-02-6,purity99,0%(massfraction).6.8 Dodecamethylcyclohexasiloxane(D6),CASRN540-97-6,purity99,0%(massfraction).6.9 n-hexane-ethylacetate50:50(volumef
26、raction)mixture,preparedbymixingequalamountsbyvolumeofn-hexaneandethylacetate.6.10 StocksolutionsofamixofcyclosiloxanesD4,D5andD6,p=lmg/1and20mg/LEXAMPLEIOmgofeachoftherespectiveOctamethylcyclotetrasiloxane(D4(6.6),decamethylcyclopentasiloxane(D5)(6.7),anddodecamethylcyclohexasiloxane(D6)(6.8)aredis
27、solvedtogetherina100mlvolumetricflask(5.5)andfilledupwithmixedsolutionofn-hexaneandethylacetate(6.9).Mixedstocksolutionsarepreparedtoobtainconcentrationsof1mg/1and20mg/1.6.11 Internalstandard,p=100mg/LTheUSeOfaninternalStandardisrequiredtoavoidmatrixeffects.1) ChemicalAbstractsService(CAS)RegistryNu
28、mberisatrademarkoftheAmericanChemicalSociety(ACS).ThisinformationisgivenfortheconvenienceofusersofthisdocumentanddoesnotconstituteanendorsementbyISOoftheproductnamed.Equivalentproductsmaybeusediftheycanbeshowntoleadtothesameresults.IS023649:2025(en)IULTCSIUC444:2025(en)Examplesofsuitableinternalstan
29、dards:Naphthalene-DS1CASRN1146-65-2;Tetrakis(trimethylsilyloxysilane,CASRN3555-47-3.Preparea100mg/1solutionoftheinternalstandardbydilutingtheinternalstandardwithn-hexane-ethylacetate50:50(volumefraction)mixture(6.9).6.12 Calibrationsolutionsofcyclosiloxanes.PrepareatleastfourcalibrationsolutionsOfP=
30、0,1mg/1top=10mg/1ofthemixofcyclosiloxanesusingthestocksolutionsf6.10),seeTabIeLTable1ExampleofcalibrationsolutionsConcentrationmg/1Volumeofn-hex-ane-ethylacetate50:50(volumefraction)mixture(6.9iVolumeofmixofcyclosiloxanes1mg/1(6.10)iVolumeofmixofcyclosiloxanes20mg/1(6.10)iVolumeofinternalstandard_10
31、0mg/1(6.11)i0,18901000100,54905000101940050105740025010104900500107 SamplingandsamplepreparationThespecimenshouldbethoroughlymixedtogetarepresentativetestportionforanalysis.Inthecaseofverydensechemical,manuallyormechanicallyshakethesampletohomogenizethecompositionofthetestspecimen.8 Procedure8.1 Sam
32、plesolutionpreparationWeigh(0,50,05)gofthetestspecimenwithananalyticalbalance(5.8)ina100mlvolumetricflask(5.5)andmakeuptovolumewithgrade1water(6.3).Closetheflaskandplaceitfor(102)mininanultrasonicbathf5.1)atastartingtemperatureof40to45.Thisprocedureisonlyapplicabletowater-solublechemicals.Otherwise,
33、usetheproceduredescribedinAnneXC.8.2 Liquid-liquidextractionPipette10mlofthesamplesolutionf8.1intoaplastictesttubef5.6)andadd1gofsodiumchloridef6.41and4gofmagnesiumsulphateanhydrousf6.5).Thenpipette10mlofn-hexane-ethylacetate50:50(volumefraction)mixture(6.9)and10lofinternalstandardf6.11tothesampleso
34、lution,closetheplastictesttubeandshakebyhandanddegas.ShakeforflO2)minonamechanicalhorizontalshakerf5.21at300cycles/min.Forcompletephaseseparationaftershaking,themixtureshallbecentrifuged(5.10)for(51)minat(3000400)rminlthenanaliquotofthesupernatantofextractionsolutionisfiltered(5.4)intoaGCsamplevial(
35、5.7).ThealiquotisthenreadyfortheGC-MSanalysis.ISO2025-Allrightsreserved8.3 InstrumentalanalysisThedetectionofthecyclosiloxanesismadeusingGC-MS.ExamplesofsuitablechromatographicconditionsaregiveninArmeXA(forGC-MS).Iftheconcentrationofthecyclosiloxanesisoutoftherangeofthecalibration,makeanappropriated
36、ilutionandanalyseagain.9 ExpressionofresultsThecontentofeachcyclosiloxaneiscalculatedasthemassfraction,w,inmilligramsperkilogram(mgkg)ofthechemicalspecimenaccordingtoFormUIa(1):whereAsisthepeakareaofeachcyclosiloxaneintheextractionsolution;Aisampeisthepeakareaofthecorrespondinginternalstandardinthee
37、xtractionsolution;CiSamPIeistheconcentrationoftheinternalstandardintheextractionsolutioninmicrogramsperlitre(gl);bistheinterceptofthecalibrationgraph;distheeventualdilutionfactor;Qistheslopeofthecalibrationgraph;Visthefinalvolumeused(0,011);misthemassofthechemicalspecimeningrams(g).10 PrecisionWitht
38、hismethoditisfeasibletoreachlimitsofquantification(LOQbelow50mg/kgforeachcyclosiloxane.TheresultsofinterlaboratorytrialstodeterminethecontentofOctamethylcyclotetrasiloxane(D4),decamethylcyclopentasiloxane(D5)anddodecamethylcyclohexasiloxane(D6)inchemicalsarepresentedinAnnexB.11 TestreportThetestrepo
39、rtshallincludeatleastthefollowinginformation:a) areferencetothisdocument,i.e.ISO23649:2025;b) type,originanddescriptionofthechemicalsample,ifpossible;c) dateofthetest;d) thetypeofGCequipmentused;e) massfractionofeachquantifiedcyclosiloxane(seeClause9),ifrequested,expressedinmilligramsperkilogram(mg/
40、kg);f) anydeviationsfromtheprocedure;g) anyunusualfeaturesobserved.AnnexA(informative)ChromatographicanalysisoperatingparametersforGC-MSA.lPreliminarycommentAstheGCequipment(5.11)ofthelaboratoriescanvary,nogeneralvalidinstructionscanbeprovidedforthechromatographicanalysis.Thefollowingparametershaveb
41、eensuccessfullytestedandused.A.2GC-MSoperatingparametersA.2.1GC-MSchromatographicconditionsColumn:5%phenylmethylsiloxane,length:30m;internaldiameter:0,25mm;filmthickness:0,25mInjectionsystem:splitless,time2minInjectiontemperature:250Injectionvolume:llCarriergas:helium,flowrate:1,5ml/minTemperaturepr
42、ogramme:50(3min)thenupto160at10oCmin,upto240at40oCmin.Totalruntime16minMSconditions:Transferline:280;ionsource:230;quadrupole:150C,solventdelay:4minMSdetection:seeTableA.lTableA.lTypicalionsforGC-MSCyclosiloxanecompoundsQuantifierionm/zQualifierionsm/zOctamethylcyclotetrasiloxane(D4)28128282decameth
43、ylcyclopentasiloxane(D5)26773,267,355dodecamethylcyclohexasiloxane(D634173,341,429AnnexB(informative)Precision:reliabilityofthemethodThedatapresentedinTableSB.landB12andBi3wereobtainedinacollaborativetrialwith12laboratoriesoffourwaterproofingfatliquors(Sample1toSample4)containingunknownlevelsofcyclo
44、siloxanes.TableB.lStatistiCaldataforQCtamChemicalsampleethylcydotetrasilXmg/kgPXaiIe(D4)OfthecollaborativetrialSRmg/kgSample135259Sample2LoQSample33485319Sample430369TableB.2Statistic,aldatafordecamChemicalsampleethylCydQPeiltaSiXmg/kgIQXaiIe-(D5)of4hecollaborativetrialSRmg/kgSample114224Sample2LoQS
45、ample31639134Sample417729TableB.3Statistic;HdatafordodecaChemicalsamplemethylcydQhexasXmg/kgiloxane(D6)OfthecollaborativetrialSRmg/kgSample110126Sample2LoQSample3917104Sample411024whereXisthemeanvalueofeachcyclosiloxane;SRisthestandarddeviationofthereproducibility;LoQisthelimitofquantification.Annex
46、C(normative)Samplepreparationfornon-water-solublechemicalsC.lPreliminaryremarkThisproceduredescribesamethodforthepreparationofaspecimensolutioninthecasethatnon-watersolublechemicals(e.g.siliconeoils)areanalysed.C.2AdditionalreagentsusedC.2.1ChloroformCASRN67-66-3,suitableforGC-MSanalysis.C.2.2Acetic
47、acid(glacial)CASRN64-19-7,purity99,0%(massfraction).C.2.3Internalstandardinchloroformp=100mg/LTheuseofaninternalstandardisrequiredtoavoidmatrixeffects.Examplesofsuitableinternalstandards:Naphthalene-D8,CASRN1146-65-2;Tetrakis(trimethylsilyloxy)silane,CASRN3555-47-3.Preparea100mg/1solutionoftheinternalstandardbydilutingtheinternalstandardwithchloroformCmjC.3SpecimenpreparationWeigh(0,50,05)gofthetestspecimenwithananalytic
