高分子化学-Polymer-chemistry5共聚-Copolymerization课件

高分子化学

Polymerchemistry高分子化学

PolymerchemistryChapter5Copolymerization共聚5.1introduction5.2copolymercomposition5.3microstructure5.4TheRateEquationofcopolymerization5.5determinationofreactivityratio竞聚率的测定5.6Q,escheme5.7ioniccopolymerizationChapter5Copolymerization5.1Copolymerizationisatypeofpolymerizationstartingfromamixtureoftwo(ormore)kindsofmonomerstoproduce“copolymners”.Theircounterpartsare“homopolymerization”and“homopolymers”startingfromonlyonekindsofmonomers.Part1IntroductionCopolymerizationisatypeof1.1ImportanceofcopolymerizationAnimportantpolymermodificationtechniqueForthepurposeof,(1)introducingproperfunctionalitiesintopolymers(2)evaluatingthemonomerreactivityinpolymerizationandthemechanismofpolymerization

1.1ImportanceofcopolymeriExamplesStyrene+Butadiene→SBRAcrylonitrile+Butadiene→NBRAcrylonitrile+Butadiene+Styrene→ABSNaAcrylate+VinylAlcohol→Waterabsorbentresin

ExamplesStyrene+Butadiene→Fromtheexamples,wegetByusingcopolymerizationtechniques,manypropertieshavebeengreatlyimproved,suchas,mechanicalstrength,elasticity,plasticity,Tg,solubility,surfaceproperties,anti-causticity,anti-aging,resolvability,andsoon.Ifnecessary,thethirdmonomershouldbeemployedtoimprovethepropertiesofpolymers.

Fromtheexamples,wegetByusTheimportantfactorsTodescribethehomopolymerization,weusethefollowingfactors,suchas,polymerizationrate,averagemolecularweightofproduct,moleculardistributionDifferentfromthehomopolymerization,wedescribethecopolymerizationbyusingthefactorsascopolymercompositionandsequencedistribution.

TheimportantfactorsTodescriSortsofcopolymersAccordingtothechainmicrostructures,thecopolymerscanbeclassifiedintofoursorts,RandomcopolymerAlternativecopolymerBlockcopolymerGraftcopolymerSortsofcopolymersAccordingtRandomcopolymer

UnitM1UnitM2Wenameitaspoly(M1-co-M2)，suchaspoly(butadiene-co-styrene)RandomcopolymerUnitM1UnitM2AlternativecopolymermonomerunitstrictlyjointonebyoneWenameitaspoly(M1-alt-M2)，suchaspoly(styrene-alt-maleicanhydride)AlternativecopolymermonomeruBlockcopolymerM1blockM2blocktherearediblock,triblockandmultiblockSuchasAB,ABA,ABCand(AB)nWenameitaspoly(M1-b-M2)or(M1/M2)blockcopolymer，suchaspoly(styrene-b-butadiene)or(styrene/butadiene)blockcopolymerBlockcopolymerM1blockM2bloGraftcopolymerbackboneBranchchainWenameitasbackbone-g-branchor(backbone/branch)graftcopolymer，suchaspoly(styrene-g-butadiene)or(styrene/butadiene)graftcopolymerGraftcopolymerbackboneBranchInthetypicalcopolymerization,therearesomeinterestingphenomena,suchas,Thedifferencebetweenthemonomerfeedratiototheproductcopolymercomposition,Somemonomerpairsaredifficulttoreactwitheachother,whilesomemonomerscanreactwithothermonomerbutnotreactwithitself.Thatisbecauseofthediscrepancyofactivitybetweendifferentkindsofmonomers.Part2CopolymerCompositionInthetypicalcopolymerizatio5.2.1Copolymercompositionequation

ChainpolymerizationInitiationPropagationtermination

M1、M2:monomerpairs~~M1*、~~M2*:reactivecenters5.2.1CopolymercompositioneqChaininitiationKi1Ki2ChaininitiationKi1Ki2ChainpropagationChainpropagationChainterminationk11M1*+M1*PolymerR11=k11tt[M1*]2t121212kM1*+M*PolymerR=ktt[M1*]2t2[M*]Chainterminationk11M1*+M1*PolAssumptionsforcopolymerizationActivityequaltheory:ThereactivityofchainendisindependentofchainlengthReactivityofagrowingchaindependsonlyontheterminalmonomerunitThemostofmonomersareconsumedduringthepropagationandnodepropagationAssumptionsforcopolymerizatiSteadystateofpropagation:Steadystateofpropagation:DeductionofcopolymercompositionDeductionofcopolymercomposiThesteadystateassumptionsonM1*、M2*ThesteadystateassumptionsodefinitiondefinitionMayo-LewisEquationInwhich,d[M1]/d[M2]:instantaneouspolymercomposition[M1]/[M2]：instantaneousmonomercompositionr1、r2：reactivityratio~~M1*+M1→

k11r1=k11/k12~~M2*+M2→k22Mayo-LewisEquationInwhich,AnotherformofMayo-LewisEquation(5－18)Definition:AnotherformofMayo-LewisEquDiscussionofMayo-LewisEquationInstantaneouscopolymercompositionNormallycopolymercompositionisdifferentfromthatofmonomerpairs(feedratio),exceptthecaseofr1=r2=1orr1[M1]+[M2]=[M1]+r2[M2]=1Therearedifferentkindsofactivecenter,suchasradical,anionicandcationicion.Ther1andr2ofsamemonomerpairsshouldbedifferentamongdifferentkindsofactivecenterFortheioniccopolymerization,thereactivityratioisgreatlyaffectedbythepropertiesofanti-ion,solventandtemperature.DiscussionofMayo-LewisEquat5.2.2ThecopolymercompositioncurveandthetypeofcopolymerizationReactivityratioRistheratiobetweentheactivityofmonomerpairsinthecompetedpropagation.r1=K11/K125.2.2ThecopolymercompositiTherelationbetweenr1andpolymerizationcharacterr1=0：onlycopolymerizationbutnohomopolymerization；0<r1<1：monomertendstohomopolymerizationandthehomopolymerizationincreasewiththerdecrease;r1=1：sameabilitybetweenhomo-andcopolymerization；

1<r1<：monomertendstocopolymerizationandthecopolymerizationincreasewiththerincrease;Therelationbetweenr1andpo①②③④①②③④Curve1.Alternatingcopolymerizationr1=0，r2=0e.g.60℃，St(r1=0.01)—maleicanhydride(r2=0)F1～f1plotCurve1.Alternatingcopolymecharacter1)Onlycopolymerizationandnohomopolymerization:k11=0,k22=02)Twokindsofmonomerunitarrangealternatively，F1、F2takehalfofchains3)Practicallyitisr1→0andr2→0insteadofr1=r2=0.Smallerr1*r2is,strongertrendsofalternativecopolymerizationshows.character1)OnlycopolymerizatCurve2.r1<1，r2<1，withazeotropepointr1=0.6r2=0.3R1=0.5R2=0.5F1～f1plotAAzeotropepointCurve2.r1<1，r2<1，withazeotrAtazeotropepointTheazeotropeisimportant,particularlyinindustry,becausethemonomerandcopolymercompositiondonotchangewithconversion,thusproducingcopolymershomogeneousincomposition.Copolymerizationsundertheotherconditionswillchangetheinstantaneouscompositionsalongthecompositioncurve.AtazeotropepointTheazeotropCurve3.Idealazeotropecopolymerizationr1=0，r2=0

F1～f1plotCurve3.IdealazeotropecopolF1=f1anddonotchangewithconversion(idealcopolymerization)

k11=k12，k22=k21，～～M1*and

～～M2*havesamereactivitywithM1andM2；e.g.：

CF2=CF2～CF2＝CFClSt～p-MSt,70℃F1=f1anddonotchangewithcCurve4.r1>1，r2<1orr1<1，r2>11050.50.11)r1>1(k11>k12)andr2<1(k22<k21)showsthatM1ismoreactivethanM2nomatterfor～～M1*and～～M2*.F1isalwayslargerthanf1andthecurveisalwaysabovethediagonal.Thesituationissimilarforr1<1，r2>1andthecurveisbelowthediagonal.Curve4.r1>1，r2<1orr1<2）asr1*r2=1(r2=1/r1),itbecomesidealcopolymerization

Inthiscase，～～M1*and～～M2*，havethesamepreferenceforaddingoneortheotheroftwomonomersreactivity.2）asr1*r2=1(r2=1/r1),Curve5.r1>1，r2>1styrene(r1=1.38)/isoprene(r2=2.05)Curve5.r1>1，r2>1styrene(r1=1Characterofcurve5Theshapeandpositionofcurve5contrarytothatofr1<1，r2<1;ThereisazeotropepointThemonomerpairsprefertohomopolymerizationratherthancopolymerize.Asr1andr2>>1,theblocksformalongthechain.Characterofcurve5Theshape5.2.3IntegratedequationforcopolymercompositionTheimportanceofcompositioncontrolonproductproperties：SBrubber：S％22～25％tyreS％↑stifftyreS％↓coldresistant↑1）Compositionisdesignedaccordingtothefinalproperties；2）Thecompositionofproductsarenormallydifferentfromthatofmaterials;3）Thecopolymercompositionchangewiththeconversion.Key:howtopreparethecopolymerwiththeexpectedcomposition.5.2.3Integratedequationfor(1）Theinfluenceofconversiononthecopolymercompositiona.Qualitativedescriptione.g.：F1～f1curve(r1<1,r2<1)AtpointA(azeotrope)(f1)A=f1，F1＝(f1)A=f1;AtpointB,(F1)BdecreasealongthecurveBOwithconversion.AtpointC,itiscontrarytothatofpointB.(1）TheinfluenceofconversionF1～f1curve(r1<1,r2<1)Conclusion：thecopolymercompositionchangewithconversion;theproductsaremixturesofcopolymerswithdifferentcomposition(compositiondistribution)F1～f1curve(r1<1,r2<1)Conclus2.IntegratedequationSkeistmethod:Forabinarysystem,totalmolarnumberofmonomerpairsisMandF1>f1AsdMofmonomerarepolymerized,theM1unitinthecopolymerchainincreaseF1dMandthemonomerratiochangetof1-df1.2.IntegratedequationSkeistminwhich,Mf1－－theM1inthematerial；

F1dM－－theM1unitinthecopolymerf1-df1－－afterdMofM1reacted，theratioofM1inthematerial;(f1-df1)(M-dM)－－unreactedM1inmaterial.Mf1－(M-dM)(f1-df1)=F1dM(5-21)inwhich,Mf1－(M-dM)(fdM.df1isneglectedandthenresettheaboveequation：

Mdf1+f1dM=F1dMWegot：SkeistEquationdM.df1isneglectedandthenr

DefinitethemoleconversionDefinitethe

(5-23a)Meyeret.Al,(5-23b)(5-23a)Meyeret.Al,(5-23Withcertainvalueofr1,r2andinitialfeedratiof01,wecalculatethevalueofC,F1,andf1

TherelationbetweenaveragecopolymercompositionandconversionC,(5-24)Withcertainvalueofr1,r2an0.20.8Molefractionconversion1－M/M001.01.0f1F1averageM1incopolymerf2F2averageM2incopolymer0.20.8Molefractionconversion5.2.4Copolymercompositiondistributionandcontrolmethods（1）CopolymercompositiondistributionA.Infigure5－4，st（r1=0.30）anddiethylfumarate（r2=0．07）azeotrope5.2.4Copolymercompositionf1=0.20f1=0.40f1=0.50f1=0.80f1=0.70Azeotropiccopolymerf1=0.57Copolymerizationofstyreneanddiethylfumarate

f1=0.20f1=0.40f1=0.50f1=0.80f1Conclusion：1.Ifthemonomerfeedratioisazeotrope,thecompositiondoesnotchangewithconversion;2.Ifthemonomerfeedratioisclosetoazeotrope,thecompositiondoesnotchangegreatly;3.Ifthemonomerfeedratioisfarfromazeotrope,thecompositionwillchangegreatlyandnowell-proportionedcopolymer.Conclusion：(2)Copolymercompositioncontrolmethods(1).one-potmethodAsr1＜1，r2＜1andthecopolymercompositionoftargetcopolymerisclosetothatoftheazeotropiccopolymer,thenthemonomerpairscanbefedatonepotaccordingtothetargetratio.e.g.：AswewanttopreparePSAwithF1＝0.55，St(r1=0.41)/AN(r2=0.04),wecanadoptone-potmethodbecauseF1’=0.62(2)Copolymercompositioncon(2)AddingthehighreactivitymonomermethodTarget：tokeepf1approachtof10method：A.half-batchaddingB.continuousadding(2)Addingthehighreactivity(a)(b)f10f10r1<1,r2<1,F1>f1,M1consumedquick，addingM1R1<1,r2<1,F1>f1,M2consumedquick，addingM2(a)(b)f10f10r1<1,r2<1,F1>f1,M1(c)f10f10F10F10c)r1>1,r2<1,normallyaddingM1，(F1>f1)d)r1<1,r2>1,normallyaddingM2，(F1<f1)(d)(c)f10f10F10F10c)r1>1,r2<1,no(3).ControlconversionmethodIfF1～Ccurvehasbeengotahead(suchas5－4,r1=0.3,r2=0.07),theazeotrope(F1)A=(f1)A=0.57(horizontalline)Curve3：Sincef10(=0.50)iscloseto(f1)A，F1slightlychangedwithC.BeforeC％reachto80～90％，stopthereaction；Curve4：f10=0.60andthesituationissimilarto3；Curve1：Sincef10(=0.20)isfarfrom(f1)A，F1changegreatlyatsmallC％.Thereactionshouldbekeptatlowconversion；Curve2：f10=0.80andthesituationissimilarto1.

Normallywecombinedbothmethod2and3！(3).ControlconversionmethodThecopolymerswithsamecompositionoftenhavedifferentmicrostructure.A.alternatingcopolymerB.bi-blockcopolymer

C.randomcopolymer(normalcase)D.graftcopolymerPart3MicrostructureandSequenceDistributionThecopolymerswithsamecompoSegmentlengthdistributionfunctionandaveragesegmentlengthByusingprobabilitymethod,theratioofdifferentlengthof(Ml)xand(M2)ysegmentsinmacro-chaincanbecalculate,whichisnamedasSegmentlengthdistribution.SegmentlengthdistributionfuSegmentlengthdistribution

1M12M14M12M13M1

～～M2

－M1

－M2－M1M1―M2―M1M1M1M1－M2M2－M1M1－M2－M1M1M1－M2～～CompetentreactionSegmentlengthdistributionReactionprobabilityP11and

P12is：P11+P12=1ReactionprobabilityP11andPsimilarlyP22+P21=1similarlyP22+P21=1TheprobabilitywhichformsxM1segment：from～～M2M1·tojoinwith（x-1）ofM1unitandthenwithM2unit

SegmentsequencenumberdistributionfunctionsimilarlyTheprobabilitywhichformsxMSegmentlengthsequenceweightdistributionfunction:theratioofmonomerunitinthechainstothetotalmonomerSegmentlengthsequenceweight

similarly：similarly：

ThenumberaveragelengthofxM1segment：TotalchainlengthTotalchainnubmbersThenumberaveragelengthof

similarlysimilarlyDiscusiononfigure5－6andtable5－3。condition：r1=5,r2=0.2,M1/M2=1TheprobabilityofdifferentlengthofM1sequence:1M1:（PM1)1=(5/6)0(1/6)=16.7%2M1:（PM1)2=(5/6)1(1/6)=13.9%3M1:（PM1)3=(5/6)2(1/6)=11.5%

………………Reftotable5－3andfigure5－6a.Discusiononfigure5－6andtaLengthofM1unit,NM1ProbabilityofxM1segment(PM1)x,%ThenumberofM1inxM1segmentx(PM1)x,%116.716.72.78213.927.84.63311.534.53.7549.639.46.0658.040.06.6766.6740.06.6775.5538.96.4984.6337.06.1793.8533.85.64103.2132.15.35200.5210.41.74300.0842.520.42400.01360.540.09500.00220.110.018…………

∑(PM1)x=100%∑x(PM1)x=600%=6100%LengthofM1unit,NM1ProbabilFigure5-5segmentdistribution(a)andunitdistribution(b)incopolymerabFigure5-5segmentdistributiFromfigure5－6a,wecanget,theshapeoffigureissimilartomolecularweightnumberdistributioncurvethemeaning：thepercentageofxM1segmentinΣxM1；16.7%of1M1…13.9%of2M1…8.0%of5M1………theratioof1M1segmentisthehighest,whichcanberefedtothehighestratioofx=1（monomer）inthemolecularweightnumberdistributioncurveFromfigure5－6a,wecanget,Accordingtotheprobabilitytheory,thecopolymercompositionratiod[M1]/d[M2]isthenubmer-averagedlengthratiobetweentwosegments.AccordingtotheprobabilitytPart4TheRateEquationofcopolymerizationInitiation,propagationandterminationTheeffectofterminationrateoncopolymerizationrate：Thechemicalcontrolledtermination;Thediffusioncontrolledtermination.Part4TheRateEquationofc5.4.1TherateequationofchemicalcontrolledterminationSincethedispearrateofmonomerisdeterminedbypropagation,theoverallpropagationrateisthesumoffourkindsofpropagation.5.4.1TherateequationofcTwokindsofsteadyasumption：1.Theconcentrationofallkindsofradicalsareinthesteadystate，then：2.Thetotalconcentrationofradicalskeepconstant,I.e.theinitiationrateequalstotheterminationrate：Ri=Rt=2kt11[M1·]2+2kt12[M1·][M2·]+2kt22[M2·]2Twokindsofsteadyasumptionφ＞1isprefertothecrossterminationφ＞1isprefertothecrosster5.4.2TherateequationofdiffusioncontrolledterminationTheterminationrateisdependsontheviscosityofsystemastheviscosityislow.Intheotherword，thechainterminationiscontrolledbychaindiffusionfromthelowconversionon.Therefore,thetotoalpropagationrateequationis：5.4.2Therateequationofdif(5-36)(5-36)Theterminationrateconstantcanberegardedasthefunctionofterminationrateconstantofhomopolymerizationasfellows,TheterminationrateconstEq.(6-29)Eq.(6-30)Figure5-7VAc-MMAsolventcopolymerization(60℃)Eq.(6-29)Eq.(6-30)Figure5-7VPart5ExperimentalEvaluationofreactivityratioItiskeytorecognize：

copolymercomposition,microstructuralsequencedistribution,copolymerizationrate,therelatedactivityofmonomerpairsDeterminationmethods：

Fromthedeterminationofcopolymercomposition,sequencedistributionandcopolymerizationconstanttotheevaluationofreactivityratio.Part5ExperimentalEvaluatio5.5.1Determinationmethodsofreactivityratio（1）FromthedeterminationofcopolymercompositionA.Atlowconversion（usually<5％or10％）B.Byusingthedifferentialequation（5-15）or(5-18)（5－18）5.5.1DeterminationmethodsofAthigherconversiontheintegralequation(5-23b)isusedinsteadofaboveequation:（5－23b）AthigherconversiontheintegTechniquesforcopolymeranalysis:elementalanalysisinfraredspectroscopyNMRGaschromatographyTechniquesforcopolymeranalyFromthedeterminationofsegmentlengthdistributionof(PM1)xand(PM2)xtocalculatethereactivityratioFromthedeterminationofsegmEssential：Toanalysisthemicrostructuredifferenceofbiadsortriadsandtetrads～M2M1M2M1M1M2M2M1M2M1M1M1M2M1M2M2M2M1M1M2～6kindsoftriads3kindsofbiads9kindsoftetradsEssential：Toanalysisthemicre.g.：ThecontentofM1M1M1,M1M1M2,M2M1M2canbedeterminedbyNMR,whicharenamedasA111,A112andA212,respectively.Byusingthefollowingequation,(PM1)3=A111/(A111+A112+A212)(PM1)2=A112/(A111+A112+A212)(PM1)1=A212/(A111+A112+A212)theP11andr1canbecalculatedaccordingtoeq.(6-22)and(6-18).Similarly,P22andr2areobtained.ThepeakscorrespondingtothedifferenttriadscanbeobservedbyNMRe.g.：ThecontentofM1M1M1,M1M

terminationiscontrolledbydiffusionrateterminationiscontrolledbybyusingsteady-stateassumption:(6-31)Kp,k11andk22canbeDeterminedbynonsteady-StatepolymerizationNon-steady-statepolymerization－－－pulsantlasertechniquebyusingsteady-stateassumpt5.5.2ReactivitycalculationmethodTodeterminethecopolymercompositionatlowconversion（1）curvefittingmethod（2）lineintersectionmethod（3）Fineman-Rossmethod(线性化法)5.5.2Reactivitycalculation

（1）curvefittingmethoddrawf1-F1curveaseriesofexperimentalf1/F1Comparedwiththecurvedrawbythepresetreactivities：r1、r2（1）curvefittingmethoddrawf1F1f1F1

（2）lineintersectionreset（5-15）：（5－39）Thelineswiththevariablevalueofr1andr2Reftofigure5-8（2）lineintersectionreset（5-Figure5-8thereactivitybylineintersectionmethod,inwhichthecircularstandthemostreasonabler1andr2Figure5-8thereactivitybyByusingtheintegralcopolymercompositionequation：（5－40）Byusingtheintegralcopolyme（3）Fineman-Rossmethod(线性化法)set：x=[M1]/[M2]y=d[M1]/d[M2]eq.（5-39）isturnedinto：

（5－41a）（5－41b）（3）Fineman-Rossmethod(线性化法)Figure5-9thereactivityofallylchloride(M1)andVAc(M2)byFRequation

treatwitheq.(5-41b)treatwitheq.(5-41a)Figure5-9thereactivityofYezrielevYezrielev5.5.3Theinfluencefactorsofreactivityr=k11/k12,thefactorswhichinfluencethekarealsoinfluencerExtrafactors：reactioncondition、Temperature、Pressure、solventIntrafactor：structurefactors5.5.3Theinfluencefactorso（1）temperature

reactivityratio:r1＝k11/k22，(5-42)Activeenergyofself-propagationActiveenergyofcross-propagationThesmalldatashowsthatthereactivityratioisnotgreatlyinfluencedbyreactivityratio（1）temperature(5-42)ActiveenA.RisnotgreatlyinfluencedbyT：Eisaslittleasc.a.20～35kJ/mol,E11-E12isevenlittle；B.r→1withTincreasesandtendstoidealcopolymerizationthatis,r1<1时，T↗，r↗→1r1>1时，T↗，r↘→1explanation：ifr1<1,thenk11<k12，E11>E12,WithT↗,k11↗>k12↗,thenk11/k12↗，ThereforeT↗，r1↗→1Thinkofthecaser1>1A.RisnotgreatlyinfluencedTable5-4theinfluenceoftemperatureonreactivityratioTable5-4theinfluenceoftem

（2）PressureSimilartotheinfluenceoftemperatureonreactivityratio,thecopolymerizationtendstoidealcopolymerizationwithpressureincreases.e.g.：ForthecopolymerizationofMMAandANat1,100,1000atm.,thecorresponding（r1·r2）valueis0.16，0.54and0.91respectively.（2）PressureSimilartoth

（3）thepolarityofsolventRadicalcopolymerization：slightlyinfluenceonr(table5-5)Ioniccopolymerization：greatlyinfluenceonpropagationrateandr,becausethepolarityofsolventinfluencethepropertiesofionpairs,theformsandtheratioofactivecenters.Table5-5thereactivityratioofstyrene(M1)-methylmethacrylate(M2)indifferentsolvent（3）thepolarityofsolventRad

(4）otherfactorsThepHofmedia：MAA/DMAEMA；ThesaltofLewisacid：InthepresenceofZnCl2,thecopolymerizationofStandMMAtendstotheidealcopolymerization.Polymerizationmethod：thecopolymerizationofstyreneandmetheneoxalicacid.(4）otherfactorsThepHofmedPart6theactivityofmonomerandQ,escheme1.Theexperimentalmethodsforcheckingtheactivityofmonomersandradicals；2.Theinfluenceofstructuralfactors,suchasresonanceeffectsandstericeffects,ontheactivityofmonomersandradicals；3.Q,eschemeisthebridgebetweentheactivityofmonomersandradicalsandcanbeestimatedthereactivityratioofmonomerpairs.Part6theactivityofmonomewecannotdistinguishtheactivityofmonomersandradicalsinthehomopolymerization.wecannotdistinguishtheac

Why?1)KpofpropagationisnotonlydependsonM,butalsoM*;2)therearelackoftheframeofreference.Why?5.6.1therelativeactivityofmonomersReciprocalofreactivityratio（1／r1）=k12／k11，Itstandfortheratioofthepropagationconstantofaradicalwithanothermonomertothatwithitsmothermonomer，Wecanuse1/r1tocomparetherelativeactivitywithaseriesofM25.6.1therelativeactivityThecopolymerizationof～～M1*withdifferentsecondmonomer：Thecopolymerizationof～～M1*wiTable5-6therelativeactivityofvinylmonomertovariouschainradicals(1/r1)BSMMAmethylvinylketoneANMAVDCVCVAcVAc*-10067202010104.41.0MMA*42.21.0-0.820.520.390.100.05S*1.71.01.40.540.0590.019Table5-6therelativeactiviThedatainthetableshowtheactivityofthemonomerstowardsthesameradicalTheactivityofmonomersinthetabledecreasefromthetoptotheend：

e.g.～～VAc*FortheconjugationsystemwiththeradicalsS*andB*,theactivityofsomemonomersisderegulation.ThedatainthetableshowtheConclusion：Theactivityofmonomerswithdifferentsubstitutegroupsareinthefollowingorder：

CH2=CHX:C6H5-,CH2=CH->-CN,-COR>-COOH,-COOR>-Cl>-OCOR,-R>-OR,-HTherelativeactivityofCH2=CHXshowstheinfluenceofXontheactivityofmonomers：

a)themonomerswithconjugationsubstitutegroup,suchasB,S,havethebiggestactivity.b)themonomerswithstrongelectron-attractedsubstitutegroup,suchasAN,MMA,alsohavegoodactivity.c)themonomerswithelectron-repulsionsubstitutegroup,suchasVAc、CH2=CHOR,hassmallestactivity.Conclusion：5.6.2therelativeactivityofradicalsfromr1=k11／k12andtheavailablekP、r1,wecancalculatek12=k11/r1=(kP/r1)（seetable5-7）K12,k1’2,k1’’2,showtherelativeactivityofseriesofradicalstowardssamemonomerM25.6.2therelativeactivityoTable5-7k12ofthereactionofchainradicalandmonomer(L·mol-1·s-1)B－

S－

MMA－

AN－

MA－

VAc－

VC－S4014515504900014000230000615000MA1302033671310209023000209000Table5-7k12ofthereactionthedataofrowsintable5-7showtherelativeactivityofseriesofradicalstowardssamemonomerE.g.thefirstrowshowstheactivityofseriesradicalstowardsmonomerBTheactivityofradicalsincreasefromlefttorightTherelationbetweentable5－6(1/r1)andtable5－7(k12=k11/r1)：Thecolumnsintable5－7showtheactivityofseriesmonomertowardsthesameradicalthedataofrowsintable5-7Conclusion：1.theactivityofmonomersarereversetothatofradicals；2.theinfluenceofsubstitutegroupsontheactivityofmonomersandradicalsareindifferentextent－－theinfluenceofradicals>thatofmonomerConclusion：

5.6.3Thestructuralfactorswhichinfluencetheactivityofmonomerstheinfluenceofsubstitutegroupofdoublebondontheactivityofmonomerandradical：

(1)conjugateeffect(2)polarityeffect(3)sterichindranceeffect5.6.3Thestructuralfactors

(1）conjugateeffectTheinfluenceofsubstitutegrouponmonomersisreversetothatofradicalsduetotheconjugateeffectIfXis－C6H5，－CH2＝CH2

，itcanformp-πconjugatestructuralelectronpairwithradicals.Thestabilityofsystem↑Theactivityofmonomerislargeandthatofradicalissmall(1）conjugateeffectTheinfl

e.g.：theactivityofstyreneandbutadieneradicalislow,Whiletheirradicalsarehigh；Iftheconjugateeffectsof－OCOCH3groupofVacisweak，theactivityofVacislowandthatofVAc.*ishigh.e.g.：theactivityofstyrenePotentialenergyNewradical1.M*+M=D2.M*+Ms=D’MorsecurvedistanceActiva