1、BRITISH STANDARD BS EN 13926:2003 Surface active agents Alkoxylated derivatives Determination of hydroxyl value N-methyl imidazole method The European Standard EN 13926:2003 has the status of a British Standard ICS 71.100.40 BS EN 13926:2003 This British Standard was published under the authority of
2、 the Standards Policy and Strategy Committee on 20 March 2003 BSI 20 March 2003 ISBN 0 580 41461 2 National foreword This British Standard is the official English language version of EN 13926:2003. The UK participation in its preparation was entrusted to Technical Committee CII/34, Methods of test f
3、or surface active agents, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the
4、 BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a contract. Users are responsible f
5、or its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK in
6、terests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 13 and a back cover. The BSI copyright date displayed in this document indicates when
7、the document was last issued. Amendments issued since publication Amd. No. Date CommentsEUROPEANSTANDARD NORMEEUROPENNE EUROPISCHENORM EN13926 March2003 ICS71.100.40 Englishversion SurfaceactiveagentsAlkoxylatedderivativesDetermination ofhydroxylvalueNmethylimidazolemethod AgentsdesurfaceDrivsalkylo
8、xylsDterminationde lindicedhydroxyleMthodelaNmthylimidazole GrenzflchenaktiveStoffeAlkoxylierteDerivate BestimmungderHydroxylzahlNMethylimidazol Verfahren ThisEuropeanStandardwasapprovedbyCENon29November2002. CENmembersareboundtocomplywiththeCEN/CENELECInternalRegulationswhichstipulatetheconditionsf
9、orgivingthisEurope an Standardthestatusofanationalstandardwithoutanyalteration.Uptodatelistsandbibliographicalreferencesconcernings uchnational standardsmaybeobtainedonapplicationtotheManagementCentreortoanyCENmember. ThisEuropeanStandardexistsinthreeofficialversions(English,French,German).Aversioni
10、nanyotherlanguagemadebytra nslation undertheresponsibilityofaCENmemberintoitsownlanguageandnotifiedtotheManagementCentrehasthesamestatusasthe official versions. CENmembersarethenationalstandardsbodiesofAustria,Belgium,CzechRepublic,Denmark,Finland,France,Germany,Greece, Hungary,Iceland,Ireland,Italy
11、Luxembourg,Malta,Netherlands,Norway,Portugal,Slovakia,Spain,Sweden,SwitzerlandandUn ited Kingdom. EUROPEANCOMMITTEEFORSTANDARDIZATION COMITEUROPENDENORMALISATION EUROPISCHESKOMITEEFRNORMUNG ManagementCentre:ruedeStassart,36B1050Brussels 2003CEN Allrightsofexploitationinanyformandbyanymeansreserved
12、worldwideforCENnationalMembers. Ref.No.EN13926:2003EEN13926:2003(E) 2 Contents page Foreword3 1 Scope 4 2 Normativereferences 4 3 Termanddefinition. .4 4 Principle4 5 Reagents.4 6 Apparatus .5 7 Sampling.5 8 Procedure .5 9 Expressionofresults . .6 10 Precision.8 11 Testreport 8 AnnexA (informative)
13、Resultsofinterlaboratorytest9 AnnexB (informative) Exampleforpotentiometricoperatingparameters.11 AnnexC (informative) Exampleforatypicaltitrationcurveanditsderivative .12 Bibliography 13EN13926:2003(E) 3 Foreword Thisdocument(EN13926:2003)hasbeenpreparedbyTechnicalCommitteeCEN/TC276“Surfaceactiveag
14、ents“, thesecretariatofwhichisheldbyAFNOR. ThisEuropeanStandardshallbegiventhestatusofanationalstandard,eitherbypublicationofanidenticaltextor byendorsement,atthelatestbySeptember2003,andconflictingnationalstandardsshallbewithdrawnatthe latestbySeptember2003. AnnexesA,B,andCareinformative. According
15、totheCEN/CENELECInternalRegulations,thenationalstandardsorganizationsofthefollowing countriesareboundtoimplementthisEuropeanStandard:Austria,Belgium,CzechRepublic,Denmark,Finland, France,Germany,Greece,Hungary,Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal, Slovakia,Spain,Sweden,
16、SwitzerlandandtheUnitedKingdom.EN13926:2003(E) 4 1Scope ThisEuropeanStandardspecifiesamethodforthedeterminationofhydroxylvalueofaliphaticandalicyclic hydroxylcompoundssuchaspolyols,sorbitanesters,plasticisersandsurfaceactiveagentalcoholsand alkoxylateswithhydroxylvaluesgreaterthan20mgKOH/g. 2 Normat
17、ivereferences ThisEuropeanStandardincorporatesbydatedorundatedreference,provisionsfromotherpublications.These normativereferencesarecitedattheappropriateplacesinthetext,andthepublicationsarelistedhereafter.For datedreferences,subsequentamendmentstoorrevisionsofanyofthesepublicationsapplytothisEurope
18、an Standardonlywhenincorporatedinitbyamendmentorrevision.Forundatedreferencesthelatesteditionofthe publicationreferredtoapplies(includingamendments). ISO607, SurfaceactiveagentsanddetergentsMethodsofsampledivision. ISO4314, SurfaceactiveagentsDeterminationoffreealkalinityorfreeacidityTitrimetricmeth
19、od. 3 Termanddefinition ForthepurposesofthisEuropeanStandard,thefollowingtermanddefinitionapply. 3.1 hydroxylvalue I(OH) numberofmilligramsofpotassiumhydroxideneededtoneutralizetheaceticacidrequiredtoesterifythehydroxyl groupsin1gofthematerial,orthenumberofmilligramsofpotassiumhydroxidecorresponding
20、tothehydroxyl groupsin1gofthematerial 4Principle Aknownmassoftestsampleisesterifiedwithanexcessofaceticanhydride/tetrahydrofuransolutionusing Nmethylimidazoleasacatalyst.Theexcessofaceticanhydrideishydrolysedandthentheformedaceticacid istitratedpotentiometricallywithethanolicpotassiumhydroxidestanda
21、rdvolumetricsolution.Thehydroxylvalueis calculatedfromthedifferenceintitrationvolumesofablanktestandthetestsample. 5Reagents 5.1 General Duringtheanalysis,unlessotherwisespecified,useonlyreagentsofrecognizedanalyticalgradeandhavebeen checkedinadvanceastonotinterferewiththeanalyticalresults. WARNINGT
22、etrahydrofuranandNmethylimidazolebeinghazardouschemicals,alltheoperationsshall beconductedunderawellventilatedfumehood. 5.2 Tetrahydrofuran,C 4 H 8 O. 5.3 Aceticanhydride ,C 4 H 6 O 3 . 5.4 Nmethylimidazole ,C 4 H 6 N 2 . 5.5 Potassiumhydrogenphthalate , C 8 H 5 O 4 K, w(C 8 H 5 O 4 K)=99%driedat(10
23、5 1)C.EN13926:2003(E) 5 5.6 Ethanol,C 2 H 5 OH. 5.7 Potassiumhydroxidestandardvolumetricsolutioninethanol , c(KOH)=0,5mol/l. Weigh66,0gofpotassiumhydroxidewithapurityof85%( m/m)tothenearest0,1ganddissolveitin250ml freshlyboiledwater.Thentransferthesolutionintoa2lvolumetricflaskandcompletetothemarkwi
24、thethanol (5.6).Allowthesolutiontostandfor24hbeforestandardization. 5.8 Acetylationreagent Carefullymix92mloftetrahydrofuran(5.2)and8mlofaceticanhydride(5.3).Thissolutionisstableforuptoone month. 6Apparatus 6.1 General Ordinarylaboratoryapparatusandthefollowing. 6.2 Potentiometer,comprisingatitrator
25、withacombinedglass/calomelelectrode,automaticburetteassembly andamagneticstirrer. 6.3 Waterbath ,capableofmaintainingatemperatureof(45 1)C. 6.4 Aircooler ,withalengthof1m. 6.5 Analyticalbalance ,withanaccurateto0,0001g. 7Sampling SamplethematerialtobetestedandstoreinaccordancewithISO607. 8Procedure
26、8.1 Standardizationoftheethanolicpotassiumhydroxidestandardvolumetricsolution Weighapproximately1gofdriedpotassiumhydrogenphthalate(5.5)tothenearest0,1mgintoa150mlbeaker anddissolveitin80mloffreshlyboiledwater. Immersetheelectrodeandamagneticstirbarintothebeaker,stirandtitratewiththepotentiometer(6.
27、2)withthe ethanolicpotassiumhydroxidestandardvolumetricsolution(5.7). Recordthevolume V o oftheethanolicpotassiumhydroxidestandardvolumetricsolution(5.7)atthefirstinflection point. Carryoutthestandardizationintriplicate. 8.2 Testportion Calculatethequantityofthelaboratorysampletobeweighed, m,express
28、edingrams,bytheequation(1): () E OH 168 I m = (1)EN13926:2003(E) 6 where I(OH) E istheexpectedhydroxylvalue,inmilligramsKOHpergramofthematerial. 8.3Determination Fillthecalculatedmassofthetestportion(8.2), m,weighedtothenearest0,1mgandnotexceeding10gintoa cleandry150mlstopperedconicalflask. Introduc
29、ewithapipette10mloftheacetylationreagent(5.8). Add2mlofNmethylimidazole(5.4)intotheflaskanddissolvethetestportion. Stopuptheflaskorconnecttheaircooler(6.4). Placetheflaskinawaterbath(6.3)at45Cfor15min. Attheendofthereactiontime,add10 mlofwater(takingcareofwashingthestopperortheaircooler). Homogenise
30、andallowtostandfor2min. Introducetheelectrodeandamagneticstirbarintotheflask,addenoughethanoltocoverthetipoftheelectrode. Titratewiththepotentiometer(6.2)withtheethanolicpotassiumhydroxidestandardvolumetricsolution(5.7)and notethevolume (V 1 )atthefirstinflectionpoint. Performthelaboratorysampleanal
31、ysisinduplicate. 8.4Blank tests Carryouttwoblanktestsatthesametimeatthedetermination,usingthesamereagents,butwithoutthetest portionandnotethevolumeatthefirstinflectionas V 2 . 9 Expressionofresults 9.1 Standardisationfactoroftheethanolicpotassiumhydroxidestandardvolumetricsolution Thestandardisation
32、factor, f,oftheethanolicpotassiumhydroxidestandardvolumetricsolution(5.6)iscalculated bytheequation(2): c M V w m f = 0 0 0 10 (2) where m o isthemassofpotassiumhydrogenphthalate(5.5),ingrams; w o isthepurityofpotassiumhydrogenphthalate(5.5),inpercent( m/m); V o isthevolumeoftheethanolicpotassiumhyd
33、roxidestandardvolumetricsolution(5.7)usedforthe standardisation(8.1),inmillilitres; M isthemolarmassofpotassiumhydrogenphthalate(5.5), M(C 8 H 5 O 4 K)=204,23g/mol; c istheconcentrationoftheethanolicpotassiumhydroxidestandardvolumetricsolution(5.7), c(KOH)=0,5mol/l.EN13926:2003(E) 7 Takeasthestandar
34、dizationfactorthemeanofthreetitrationsperformedaccordingto8.1. 9.2 Hydroxylvalue Theexperimentalhydroxylvalue, I(OH) o ,inmilligramsofKOHpergramofthetestportion,iscalculatedbythe equation(3): ()( ) m f c V V I o 11 56 OH 1 2 , - = (3) where V 2 isthemeanvolumeoftheethanolicpotassiumhydroxidestandard
35、volumetricsolution(5.7)usedfor theblanktests(see8.4),inmillilitres; V 1 isthevolumeoftheethanolicpotassiumhydroxidestandardvolumetricsolution(5.7)usedforthe determination(see8.3),inmillilitres; c istheconcentrationoftheethanolicpotassiumhydroxidestandardvolumetricsolution(5.7), c(KOH)=0,5mol/l; f is
36、themeanofstandardisationfactorofethanolicpotassiumhydroxidethestandardvolumetric solution(5.7)from9.1; m isthemassofthetestportion(see8.3),ingrams. Forsamplescontainingfreeacidity,thehydroxylvalue, I(OH),iscalculatedbytheequation(4): ()()AV I I o + = OH OH (4) where () o I OH istheexperimentalhydrox
37、ylvalue,inmilligramsofKOHpergramofthetestportion; AV istheacidityvalueofthesampleinaccordancewithISO4314orequivalent,inmilligramsofKOHper gramofthetestportion. Forsamplescontainingfreealkalinity,thehydroxylvalue, I(OH),iscalculatedbytheequation(5): ()() BV I I - = o OH OH (5) where I(OH) o istheexpe
38、rimentalhydroxylvalue,inmilligramsofKOHpergramofthetestportion; BV isthealkalinityvalueofthesampleinaccordancewithISO4314orequivalent,inmilligramsofKOH pergramofthetestportion.EN13926:2003(E) 8 10Precision 10.1 Repeatabilitylimit Theabsolutedifferencebetweentwoindependentsingletestresults,obtainedus
39、ingthesamemethodonidentical testmaterialinthesamelaboratorybythesameoperatorusingthesameequipmentwithinashortintervaloftime, willnotexceedtherepeatabilitylimit, r, inmorethan5%ofcases. TypicalprecisiondataobtainedinaringtestaregiveninannexA. 10.2Reproducibilitylimit Theabsolutedifferencebetweentwoin
40、dependentsingletestresults,obtainedusingthesamemethodonidentical testmaterialindifferentlaboratoriesbydifferentoperatorsusingdifferentequipment,willnotexceedthe reproducibilitylimit, R,inmorethan5%ofcases. TypicalprecisiondataobtainedinaringtestaregiveninannexA. 11 Testreport Thetestreportshallinclu
41、dethefollowinginformation: a) allinformationnecessaryforthecompleteidentificationofthesample; b) areferencetothisEuropeanStandard; c) thetestresults; d) detailsofanyoperationsnotspecifiedinthisEuropeanStandard,andanyoperationsregardedasoptional,as wellasanyincidentslikelytohaveaffectedtheresults.EN1
42、3926:2003(E) 9 Annex A (informative) Resultsofinterlaboratorytest TheinterlaboratorytestwascarriedoutbyCESIO/AISEin1998.Theprecisiondatawereevaluatedinaccordance withISO 57252.Foursampleswereanalysedfourtimesby13 laboratories.Thesesamplesareshownin TableA.1. TableA.1Testsamples Sample Designation A
43、Isotridecanole+7EO B Sorbitanmonolaurate C PO/EOblockcopolymer D Laurylalcohol TheringtestresultsaregiveninTablesA.2andA.3. TableA.2Resultsofinterlaboratorytestconcerningtheexperimentalhydroxylvalues, I(OH) o Designation SampleA SampleB SampleC SampleD Numberoflaboratoriesparticipating 12 13 13 13 Numberoflaboratoriesnoteliminated 12 9 9 12 Totalnumberofvalues(withoutoutliers) 48 36 36 48 Meanvalue,inmgKOH/g 116,34 339,18 49,18 299,93 Repeatabilitystandarddeviation, s r ,inmgKOH/g 0,944 1,42 0,35 2,65 Repeatabilitylimit ,r :( r =2,8x s r
