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Synthesis

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Synthesisis

    Synthesis

1304Zhaneta1./JZhejiangUnivSciA20089f9J:13041308

    ;JournalofZhejiangUniversitySCIENCEA

    ;ISSN1673?565X(Print);ISSN1862?1775(Online) ;wwwzjueducn~zus;wwwspringerlinktom

    ;EmaikjZUS@zueducn

    ;Synthesisofpoly[methyl(3,3,3trinu0r0pr0py1)sil0xane

    ;b-poly(ethyleneoxide)blockcopolymers

    ;Xiao.1iZHAN,BiCHEN,Qing.huazHANG

    {l,Ling.minYI,BoJIANG,Feng.qiuCHEN

    ;(CollegeoJ‟MaterialsScienceandChemicalEngineering,ZhejiangUniversity,Hangzho

    u310027,China)

    ;(MOEKeyLaboratoryofAdvancedTextileMaterialsandManufacturingTechnology,Zh

    ejiangSciTechUniversity,

    ;Hangzhou310018,China)

    ;Email:qhzhan~;@zju.edu.cn

    ;ReceivedMay3,2008;revisionacceptedJune13,2008 ;Abstract:Aseriesofnewamphiphilicpoly[methyl(3,3,3trifluoropropy1)siloxane]

    bpoly(ethyleneoxide)(PMTFPSbPEO)

    ;diblockcopolymerswithdifferentratiosofhydrophobicsegmenttohydrophilicsegmentw

    erepreparedbycouplingreactionsof

    ;endfunctionalPMTFPSandPEOhomopolymers.Copolymerswereshowntobewellde

    finedandnarrowmolecularweight

    ;distribution(MWD)(1.07

    1.3)bycharacterizationssuchasgelpermeationchromatography(GPC)andH.nudearmagn

    etic

    ;resonance(HNMR).

    ;Keywords:Blockcopolymers,

    ;doi:10.1631/j~us.A0820162

    ;INTR0DUCT10N

    ;Polysiloxanes,Fluoropolymers,

    ;Documentcode:A

    ;Polysiloxane.basedcopolymers,asweknow, ;exhibituniquepropertiessuchashighhydrophobicity ;andflexibility,opticaltransparency,biocompatibility, ;etc.Thesecharacteristiesmakepolysiloxanesinter. ;estingasbloc:ksforthepreparationofamphiphilic ;copolymerswithpropertiesdifferentfromthoseof ;manyotherpurelyorganicpolymers.Aspecialex? ;ampleofamphiphiliccopolymersbasedonpolysi‟

;1oxaneistheso.called”superspreaders”consistingof

    ;trisiloxanesandpolyethers(RosenandWu.2001:Wu ;andRosen2002).Theremarkablesurface.active ;propertiesofthe‟‟superspreaders”havereceived

    ;muchattention.Severalresearchers(Lineta1..1994; ;Kickelbickela1.,2003a;2003b)alsocarriedoutde. ;tailedinvestigationintothesolutionpropertiesof ;copolymerscomprisingpolysiloxaneandpolyether. ;Theirpotentialtoaggregateinaqueoussolutionswas ;Correspondingauthor

    ;ProjectsupportedbytheNationalNaturalScienceFoundationof ;China(No20606029)andthePostdoctoralScienceFoundationof ;ChinafNo20070420230)

    ;Synthesis,Polyethyleneoxide

    ;CLCnumber:TQ31;063

    ;shownbythesestudiesandspontaneousvesiclefor‟

    ;mationswerereportedforamphiphilicblockco. ;polymerscomprisingpoly(dimethylsiloxane)and ;poly(ethyleneoxide)(PEO).Ontheotherhand,po? ;lymerscontainingfluorinatedalkylsidechainshave ;alsoattractedgreatattentionduetotheiramazing ;properties(Zhangeta1.,2007),suchashighchemical ;andthermalstability,outstandinganti.adhesiveand ;oil.repellentproperties.1owrefractiveindexandlow ;dielectricconstant.Incorporationoffluorinatedalkv1 ;groupintothepolysiloxanechainwillresultinpoly? ;siloxanewithmanypropertiesevensuperiorto ;poly(dimethylsiloxane).Hence,betterperformances ;canbeanticipatedforamphiphiliccopolymersbased ;onfluorinatedpolysiloxaneinsteadofpoly.(dime? ;thylsiloxane).Higherincompatibilitybetweenhy? ;drophobicandhydrophilicsegmentswillalsobring ;aboutdifferencesinsolutionbehaviorsandisworthy ;OfinVestigatiOn.

    ;However,fluorinatedpolysiloxane..basedam.. ;phiphiliccopolymerswererarelyreported.Thismay ;becausedbythedifficultyofachievingnarrowmo. ;1ecularweightdistribution(MWD)fluorinatedpoly? ;

    ;Zhaneta1./JZhejiangUnivSciA20089f9J:13041308

    ;siloxanes.Severe‟‟back—biting‟‟andredistribution

    ;sidereactionstakeplaceinthering?-openingpolym?- ;erization(ROP)offluorocontainingcyclosiloxane,

    ;resultinginverylimitedpoly(fluorinated)siloxane

;homopolymersf1O%2O%)withbroadMWDwhen

    ;equilibratedfYieta1.,2005).

    ;Inourwork,aseriesofamphiphilicdiblock ;copolymerscomprisingpoly[methyl(3,3,3trifluoro

    ;propy1)siloxane](PMTFPS)andPEOwithadifferent ;ratioofthehydrophobicsegmenttothehydrophilic ;segmentwereprepared.TheMrvVDsOfPMTFPSb

    ;PEOdiblockcopolymerssynthesizedwerecontrolled ;between1.O7to1.3Obvcarefulselectionofpolym

    ;erizationandpurificationmethods.

    ;EXPERIMENT

    ;Materials

    ;1,3,5trimethyl1,3,5tris(3,3,3trinuoropropy1)

    ;cyclotrisiloxane(F3)(99.9%,Shanghai3FCo.)was ;firstdriedover3Amolecularsieves,thenrefluxedin ;CaH,for2handfnallyvacuumdistilledintoam

    ;poules.n-butyllithium(BuLi)inhexanef2mol/L) ;waspurchasedfromAldrichandtitratedbeforeuse ;(GilmanandCartledge,1964).Tetrahydrogenfuron ;(THF)(99%,SinopharmChemicalReagentCo.)was ;refluxedinsodiumuntilitturnedbluewiththeaddi

    ;tionofdiphenylketone.Dimethylchlorosilane(98%, ;waspurchasedfromAldrichanddistilledbeforeuse. ;Speier‟scatalystwasprepareddissolving

    ;H2PtC166H20(SinopharmChemicalReagentCo.,AR) ;inisopropanoltoform0.O1mol/Lsolution.Toluene ;(99.5%.SinopharmChemicalReagentCo.)wasdis

    ;tilledfromsodium.Methanol(99%.Sinopharm ;ChemicalReagentCo.1wasusedasprecipitator.Allyl ;terminatedPEOwaskindlYprovidedbyClariant ;Corporationandcharacterizedbygelpermeation ;chromatography(GPC)(<1.2)beforeuse. ;Othersolventsusedintheexperimentswerepurified ;accordingtostandardmethods.

    ;SynthesisOfSi.HfunetionalPMTFPSho.

    ;mopolymers

    ;Ahighvacuumtechniquewasusedtomaintaina ;“pure”reactionenvironmentr1O_jPa)beforeArwas

    ;filiedtoprotectthereactionsystem.F/BuLiwasfirst

    ;transferredtothereactorundertheprotectionofAr. ;1305

    ;FwasdissolvedinTHFtoformaclearsolutionand ;subsequentlythesolutionwasaddedintothereactor ;tostartthereaction.TheadditionoftheTHFsolution

    ;ofFwasdividedintotwosteps:(1)acertainamount ;ofsolutionwasaddedr1.2molF3/molr/-BuLi)and ;stirredfor1hat0.C;(2)theresidualsolutionwas ;addedandstirredforanother2hat0.C.Inbothsts,

    ;monomerconcentrationwaskeptabove1.3mol/Lto ;yieldnarrowMWDhomopolymersaccordingtoour ;previouswork(Yieta1.,2005).Dimethylchlorosilane ;wasaddedtoterrainatethereactionandthesolution ;wasstirredforanotherl2hatroomtemperature.The ;resultantmixturewascentrifugedfor10minand ;separated.Theorganicphasewasvacuumdistilledto ;removeremainedsolvent.

    ;HNMR(500MHz,CDCl3,:0-0.22m,

    ;OSi(Cg3)2O],0.58-0.65[t,CH3CH2CH2CH2Si], ;0.70-0.81[t,CF3CH2CH2Si],0.85-0.95[t,C/-/3CH2

    ;CH2CH2Si],1.25-1.40[m,CH3CH2CH2CH2Si], ;1.90-2.15[t,CF3CH2CH2Si],4.73-4.75[s,sin]. ;PreparationofPMTFPS-b-PE0blockeopolymers ;A5O%(w/w)toluenesolutionofSiHtermi

    ;natedPMTFPShomopolymerandallylterminated ;PEOhomopolymerr1.2mol/molSiHgroups)was

    ;stirredaggressivelyatroomtemperatureinnitrogen ;atmosphere.Thepolymerswerecoupledbyhydrosi

    ;lationreactionapplyingl0-4mol/moldoublebond ;Speier‟scatalyst.Thesolutionwasheatedto8O.C

    ;andstirredfor24h.Atierthecompletionofthehy

    ;drosilationreaction,thesolventwasvacuumdistilled. ;Productswerepurifiedusingmethanolasthepre

    ;cipitator.

    ;H-NMR(500MHz,CDC13,o3:0-0.22m,

    ;OSi(CH3)2O],0.58-0.65[t,CH3CH2CH2CH2Si], ;0.70-0.81[t,CF3CH2CH2Si],0.85-0.95[t,CH3CH2

    ;CH2CH2Si],1.25-1.4O[m,CH3CH2CH2CH2Si], ;1.90-2.15[t,CF3CH2CH2Si],3.38-3.42[CH30

    ;(CH2)20],3.50-3.8O[O(CH2)20].

    ;Characterizationmethods

    ;GPCanalysiswasperformedonaWaters

    ;1525/2414GPCsystemconsistingofaWaters1525 ;binaryhigh-performanceliquidchromatography ;pump,aWaters717Plusautosampler,threeWaters ;Styragelcolumns(StyragelHR2.HR3andHR4)anda ;Waters2414refractiveindexdetector.andTHFwas

    ;usedaseluentataflowrateof1.0ml/minat40.C. ;

;1306Zhanetal/dZhejiangUnivSciA20089(~:13041308

    ;Thecalibrationcurvewasmadewithpolystyrene(PS, ;standardsfWatersCo.1.ForPE0homopolymersthe ;molecularweightscalculatedwiththePScalibration ;weretransformedintoPEOmolecularweightsvia ;“universalcalibration”(Grubisiceta1..1996).Mark—

    ;Houwinkconstantsusedfor”universalcalibration”

    ;were;Kps=0.0288,s=O.61,KpEO=0.0135andOtPEO= ;O.78.wheretheunderscriptcorrespondtorespective ;homopolymers(Roberteta1..1997).

    ;HNMRanalysiswasconductedwithaBruker ;500MHznuclearmagneticresonancespectrometer ;(AdvanceDMX500)andwascarriedoutwitha5% ;(w/w)solutioninCDC1atroomtemperature. ;Infraredspectraofthepolymerswererecorded ;onaNicolet5700Fouriertransforli1inflared(FT-IR1 ;instrument.ThepolymerfilmswerecastontoKBr ;diskstobeanalyzed.

    ;RESUISANDDISCUSSION

    ;SiHfunctionalPMTFPShomopolymerswere ;preparedviaanionicROPofF1terminatedwithdi

    ;methylchlorosilane.ApplyingSpeier‟scatalysttoa

    ;solutionofpurifiedSiHfunctionalPMTFPSandallyl ;te:rminatedPEOhomopolymers,avarietyofamphi

    ;philiccopolymersconsistingofPMTFPSandPEO ;withdifferentblocklengthsweresynthesized(Fig.11. ;Asweknow,thecontroloftheMWDOfeach

    ;blockiscriticalforthepreparationofblockcopoly

    ;merswithnarrowMWD.Howeve~formanyROP ;processes.ifmonomerconversionisgreaterthan85%, ;backbitingreactionswerenolongerneglectable(El

    ;kinsandLong,2004).Inordertominimizebackbiting ;reactionsandachievenarrowdistributedPMTFPS ;homopolymers,conversionsofourreactionswere ;limitedto8O%.Theinfluenceofpolymerization ;F3CCH2CH2/

    ;,

    ;\

    ;F3CcHO/

    ;(F3)

    ;I

    ;ClSiH

    ;iCH2CH2CF3BLi

    ;\

    ;conditionsonthehomopolymerhasbeencarefully ;studiedinourpreviousworkusingpoly(styreneli

    ;thium)(PSLi)asinitiator(Vieta1.,2005).High ;monomerconcentrationwasshowntoeffectively ;inhibitbackbitingandredistributionsidereactions. ;ThemonomerconcentrationforouranionicROPs ;waskeptabove1.3mol/L.ThepurityofPMTFPS ;homopolymerswasprovedbyGPCanalysis.No ;monomerresiduesweredetectedafterthepurification ;procedureinthesehomopolymers.

    ;ThecouplingreactionbetweenpurifiedSiH

    ;functionalPMTFPSandallylterminatedPEOho

    ;mopolymerswasfollowedandthecomparisonOf ;HNMRspectraofPMTFPShomopolymerand

    ;PMTFPSbPEOdiblockcopolymerwasshownin ;Fig.2.AscanbeseenSiHgroupresonancelocated

    ;around4.7disappearedcompletelyaftertheCOU

    ;plingreactionwhichsuggestedthecompletenessof ;thehydrosilationreaction.Andalso,thepeakslocated ;around0.6assignedtothemethylenegroupbonded ;tosiliconnearlydoubledafterthecouplingreaction, ;whichshowedanothersupportfortheSuccessful ;preparationofPMTFPSbPEOdiblockcopolymers.

    ;Newlyformedpeakscorrespondedtohydrogenon ;thePEOchain.PropertiesofamphiphilicPMTFPS

    ;bPEOdiblockcopolymersaresummarizedin11ablel ;PMTFPSbPEOdiblockcopolymerswithMWDs

    ;rangingfrom1.O7tOl-3Oweresuccessfullysynthe

    ;sized.

    ;NotethatMnvaluescalculatedbyGPCcharac