考研-浙大高分子物理講稿2aggregate structure of polymers

PolymerPhysics高分子物理2AggregateStructureofPolymers

高分子聚集態(tài)的結構2.1Introduction引言2.1.1Conceptofaggregatestate

聚集態(tài)結構的內涵AggregatestateArrangementandstackingofdifferentpolymerchains.Aggregatestateincludes晶態(tài)Crystallinestate液晶態(tài)Liquidcrystallinestate非晶態(tài)Amorphousstate取向態(tài)Orientationstate高分子的結構StructureofPolymers鏈結構ChainStructure聚集態(tài)結構AggregateStructure織態(tài)結構Morphology晶態(tài)結構CrystallineStructure無定型態(tài)結構Amorphousstructure2.1.2Interactionsbetweenpolymermolecules高分子的分子間作用力

covalentbondinteractionnon-covalentbond

vandeWallsforceHbond高分子由于分子間的相互作用而堆砌在一起Electrostaticforce(靜電力):

1.2104~2.1104J/molInductionforce(誘導力)：0.6104~1.2104J/molDispersionforce(色散力)：0.08104~0.84104J/mol偶極矩極化率電離能分子間距離vandeWallsforceTotalvandeWallsforce:2～8kJ/molC－Cbondenergy:

347kJ/molAssuming：PE’sDP=104，Intermolecularinteractionforce:Ef>2*104kJ/molC－Cbondenergy:EJ=347kJ/molEf>EJWhenasinglePEchainispullout,2*104kJ/molenergy(vandeWallsforce)mustbee，whichcanleadtobreakageofC-Csinglebond.

So,novaporstateforpolymer.InteractionforcebetweentheHatominX——HbondandanotherYatomwithlargeelectronegavity.Electronegativity：

H:2.1O:3.5N:3.0F:4.0Strength：15~35kJ/molFeatures：directivityandsaturabilityX——H┄┄YHydrogenbond氫鍵HbondBondlength(nm)Bondenergy(kJ/mol)F—H…F0.2428O—H…O0.2718.834.3N—H…F0.2820.9N—H…O0.2916.7N—H…N0.315.44O—H…Cl0.3116.3C—H…N13.7Cohesiveenergydensity

高分子的內聚能密度Cohesiveenergy：Theenergytoremove1molliquidorsolidmoleculesoutoftherangeofintermolecularinteractionforce.HV:

摩爾蒸發(fā)熱Cohesiveenergydensity：

Cohesiveenergyinunitvolume.HS:摩爾升華熱(:摩爾體積)CohesiveenergydensityoflinearpolymersPolymerNameCED(J/m3)PEPolyethylene259PiBPolyisobutylene272NRNaturalrubber280BRButadienerubber276SBRStyrene-butadienerubber276PSPolystyrene305PMMAPoly(methylmethacrylate)347PVAcPoly(vinylacetate)368PVCPoly(vinylchloride)381PETPoly(ethyleneterephthalate)477Nylon66Polyamide66774PANPolyacrylonitrile992RubberPlasticsFiber2.2TheCrystallineState高分子的晶態(tài)結構Differencebetweencrystallizationofpolymersandsmallmolecules:

Polymerisnot100%crystalline!crystallinity(結晶度)：

fractionofcrystallinephase

weightpercentagecrystallinity volumepercentagecrystallinity①②③1a2a2b3a3cABCdAB+BC=2dsinq2dsinq=nlq2.2.1MethodsofdeterminingcrystallinitywideangleX-raydiffraction(WAXD)X－衍射BraggequationDistancebetweensuccessiveidenticalplanesofatomsinthecrystal

X-raywavelength

Anglebetweenthex-raybeamandtheseatomicplanes

Anywholenumber

樣品差式掃描量熱法(DSC)

Differentialscanningcalorimetry(Xcw%)Hf:

實測熔融焓Hf0:100%結晶時的熔融焓冷結晶峰熔融峰玻璃化轉變(i)XcvMeasuredbydensity

(ii)XcwQuestion:Whichislarger,XcworXcv?Notice：Thevaluesofcrystallinitymeasuredbydifferentmethodsmayhavealargedifference.Usually：

XcWAXD>()Xcdensity>XcDSC2.2.2

Unitcellandconformationofpolymerchainincrystalsspherulite fibrillarbranching helicallamellaewithinfibrils1mm(POM)1m(AFM)500?(AFM,TEM) crystallattice individuallamellarstacks 1?(WAXD) 100?(SAXS)maintypesofcrystalsystemCrystalsystemLatticeconstantCubic立方a=b=c;===90Hexagonal六方a=b≠c;==90;=120Tetragonal四方a=b≠c;===90Rhombohedral(Trigonal)三方a=b≠c;==≠90Orthorhombic正交a≠b≠c;===90Monoclinic單斜a≠b≠c;==90;≠90Triclinic三斜a≠b≠c;≠≠≠90abc高分子無此晶系caxis:polymerchaindirectionUnitcell(晶胞)：ThesmallestrepeatingunitofcrystalstructurewithparallelepipedshapeMillerindices

(hkl)abcc/2a/32b/3(1)interceptofcrystallineplaneinaxes(2)removalofunit，gettingreciprocalandreductiontocommondenominator(3)removalofdenominatorSelectedcrystallographicdataPolymerCrystalSystemLatticeConstantNMolecularConformationCrystalDensity,g/cm3a,?b,?c,?PolyethyleneOrthorhombic7.4174.9452.5472PZ211.00Monoclinic8.092.534.79107.92PZ210.998PolytetrafluoroethylenePseudohexagonal5.595.5916.88119.31H1362.35Trigonal5.6619.501H1572.30Orthorhombic8.735.692.622PZ212.55Monoclinic9.505.052.62105.52PZ212.74it-PolypropyleneMonoclinic6.6520.966.5099.34H310.936Hexagonal19.086.499H310.922Trigonal6.386.331H310.939it-PolystyreneTrigonal21.906.656H311.13cis-1,4-PolyisopreneMonoclinic12.468.898.10924Z201.02PolyvinylchlorideOrthorhombic2PZ211.42PolytetrahydrofuranMonoclinic5.598.9012.07134.22PZ211.11Nylon6Monoclinic9.5617.28.0167.54PZ211.23Monoclinic9.3316.884.781212H211.17Nylon66Triclinic4.95.417.248.57763.51PZ101.24Triclinic4.98.017.29077672PZ101.248Nylon610Triclinic4.955.422.44976.563.51PZ101.157Triclinic4.98.022.49077672PZ101.196Poly(ethyleneterephthalate)Triclinic4.565.9410.7598.51121P1.455Forpolymerchainswithnosidegroup(PE)orwithsidegroupofsmallsizeorwithstrongintermolecularinteraction(polyester，polyamide，PC,PVA).Polymerchainsadoptall-transconformation.Thelowestenergyof

polymerchains.Advantageoustodensepackingincrystals.planezigzag(平面鋸齒結構)Note:

POMandPEOexhibithelixconformationincrystalPEOrthorhombic

正交晶系Helix(螺旋形結構)Forpolymerchainswithsidegroupoflargesize,gaucheconformationsometimesisadoptedtoreducesterichinderanceandfreeenergy.

Forexample：

isotacticPP(H31),poly(o-methylstyrene)(H41),isotacticPMMA(H52)，

isotactic

poly(4-methylpentene-1)(H72),poly(m-methylstyrene)(

H118).IsotacticPPThepolymerchainsarenotinthesameplane,butexhibitahelixconformationinthethree-dimensionalspace.Everythreerepeatingunitsformsahelixwithaperiodiclengthl＝6.50?.H31:H：Helix3：numberofrepeatingunits1：numberofturnswithinaperiodiPP(等規(guī)聚丙烯)：Monoclinic單斜2.2.3Modelsofcrystallinepolymers高分子晶態(tài)結構模型TheFringedMicelleModel纓狀微束CrystallinephaseAmorphousphase100?Contourlength=2000?Bryant1940AtacticPPIsotacticPPAl■

Observation：★

Bothdiffractionpatternanddiffusedcircleareobserved.★

ThemeasuredsizeofcrystallinedomainisabouthundredAstrongs(muchsmallerthanthelengthofpolymerchain).■

Model：★

co-existenceofcrystallineandamorphousdomains★

smallsizeofcrystallinedomain(onepolymerchaincantraverseseveralcrystallinedomains)★

randomorientationofcrystallinedomains■

Reasonable：★

Theapparent

density<densityofunitcell★

meltingrangeduetodifferentsizesofcrystallinedomains★

Arcdiffractionpatternandbirefringenceaftertensiledrawing■

Unreasonable：★

Crystallineandamorphousdomainscanseparate.★

Howislamellarandspheruliticmorphologyformed?TheFoldedChainModel折疊鏈CrystallinephaseAmorphousphaseKeller1957110~140?Singlecrystals近鄰折疊■

Observations:★

PEsinglecrystalswithtensofmicrometerssizeand100?thickness(TEM).★

ThicknessofsinglecrystalisindependentofMw.★

Polymerchainsareperpendiculartothelamellae(XRD).■

Model：★

Polymerchainsregularlyfoldandformlamellarcrystalsof100?thickness.■

Reasonable：★

Formationoflamellarandspheruliticmorphology■

Unreasonable：★

Thedensityofsurfaceissmallerthanthebulkofsinglecrystals.★

Thelamellarcrystalscanstackintofibrilstacksandthenspherulites.規(guī)則近鄰折疊近鄰松散折疊★

Crystallizationofsomepolymertakesplaceveryfast(suchasPE).Regularfoldingisdifficulttoreachsinceitisarelaxationprocess.★Canexplainwhythedensityofsurfaceissmallerthanthebulkofsinglecrystals.■

Unreasonable：■

Reasonable：TheSwitchboardModel

插線板CrystallinephaseAmorphousphaseFloryCrystalsfrommelt小角中子散射(SANS)測量聚合物的分子尺寸聚合物結晶過程熔體結晶態(tài)PE從熔體中快速冷卻(淬火)0.0460.046PP急劇冷卻0.0350.034淬火后在137oC保溫(退火)0.0350.036i-PS在200oC下結晶1h0.0220.024~0.029近鄰折疊插線板模型熔體■

Observation：★

ThegyrationradiusofPEchainsincrystalissimilartothatinthemelt.(Inthecrystalspolymerchainsbasicallyretaintheconformationinthemelt,butlocallyadjustedtoenterthecrystals.)■

Model：★

Amorphousdomainsonthesurfaceoflamellae.★

Theadjacentpolymerchainsegmentsinthecrystalscanbefromthesame(butnon-adjacentsegments)ordifferentpolymerchains.★

Afterthepolymerchainenteralamellarcrystal,itcantraverseintoanothercrystalorre-enterthesamecrystalatnon-adjacentposition.Regularityofthemodels

Effectofcrystallizationconditions

Effectofpolymermicrostructure

adjacentre-entrymodel>switchboardmodel

>fringedmicellemodelfromdilutesolution： ~100%adjacentre-entryfrommelt：~70%adjacentre-entryquench： fringedmicellehomopolymer：adjacentre-entryorswitchboardrandomcopolymer：fringedmicelle2.2.4Morphologyofpolymercrystals高分子晶體的形態(tài)Lamellar-shapedsinglecrystals

單晶t聚乙烯的空心棱錐結構FormationofpolymersinglecrystalCrystallizeveryslowlyfromextremelydilutesolution(0.01～0.1%)

(butsometimescanalsobeformedfromthemelt)AFMimagesofisotacticPScrystalsin11nmthickfilmindifferentTc.210oC,4h205oC,4h200oC,4hDendriticcrystal(樹枝狀晶)Higherconcentration(0.01～0.1%)，lowerTc.Diffusioncontrolled.PEPEOExtendedChainCrystals

伸直鏈晶體Polyethylene226C,4800atm,8hrCrystallinity=97%Density=0.993830000?Highpressureandhightemperature.Themoststableinthermodynamic.FibrilCrystals

纖維狀晶體Inflowfield,polymerchainsextendandstackalongflowdirection.StringCrystals

串晶溶液低溫，邊結晶邊攪拌。shish-kebabstructurespherulite(球晶)Polarizedopticalmicroscopy(偏光顯微鏡)MalteseCrossBranchingspheruliteofiPPSpheruliteFebrileLamellar晶迭的形成caLaamorphousccrystallineLlongperiodNegativespherulite：radialrefractiveindex<normalrefractiveindex(smallbranchingangle)Positivespherulite：

radialrefractiveindex>normalrefractiveindex(largebranchingangle)ConstantgrowthrateinradialdirectionPolymerchainperpendiculartoradiusMaltesecrossbyPOMConsistinginfibrilsandstacksCrystallinity<100%Diameterfrom0.1mmto1cmCharacteristicsofspheruliteControlofspherulitesize(1)Crystallizationrate:Tcorcoolingrate(2)Microstructure:randomcopolymer(3)Nucleationagent:smallersize

HavingeffectsontransparencyandmechanicalpropertiesGrowthofspheruliteobservedbyPOM0s30s60s90s120sbandedspherulite(條帶狀球晶)smallanglelaserlightscattering小角激光散射RadiusofspheruliteWavelengthScatteringanglecorrespondingtomaximumscatteringintensityVvHvaxialiteplateletSpheruliteisnottheonlymorphologyofpolymermacro-crystals!

2.3Amorphousstate無定型態(tài)結構2.3.1Aboutamorphouspolymers

關于無定型高分子Theamorphousstateisdefinedasacondensed,non-crystallinestateofmatter.ManypolymersareamorphousunderordinaryuseconditionsPolystyrenePoly(methylmethacrylate)Poly(vinylacetate)CrystallinepolymerseamorphousabovetheirmeltingtemperaturesPolyethylenePolypropyleneNylonGlassyLiquidflowRubberyplateauGlasstransitionRubberyflowlgE,PaTemperatureTm657438910AmorphouspolymersCrystallinepolymersPhysicalstateofpolymers

高分子的物理狀態(tài)FromamorphousphaseQuestionsofinterest感興趣的問題Solidsorliquid?Water:liquid,disorderedCrystallinepolymer:solid,ordered(regular)Amorphouspolymeringlassystate:solid,disorderedPossibleresidualorder?Onthesimplestlevel,thestructureofbulkamorphouspolymershasbeenlikenedtoapotofspaghetti(意大利式細面條),wherethespaghettistrandsweaverandomlyinandoutamongeachotherOurknowledgeoftheamorphousstateremainsveryplete,andthatthisandotherareasofpolymersciencearethesubjectsofintensiveresearchatthistime2.3.2Majororder-disorderarguments

有序－無序之爭OrderDisorderConceptualdifficultiesindensepackingwithoutorderRubberelasticityofpolymernetworksAppearanceofnodulesAbsenceofanomalous(異常)thermodynamicdilutioneffectsAmorphoushalosintensifyingonequatorialplaneduringextensionRadiiofgyrationthesameinbulkasin-solventsNonzeroMooney-RivlinC2constantsFitofP()forrandomcoilmodeltoscatteringdataElectrondiffractionlateralorderto15-20?Rayleigh-Brillouinscattering,x-raydiffraction,stress-opticalcoefficient,etc.studiesshowingonlymodest(ifany)short-rangeorder2.3.3Modelsofamorphouspolymers

無定型高分子模型PrincipalsDescriptionofModelH.MarkP.J.FloryRandomcoilmodel;chainsmutuallypenetrableandofthesamedimensionasin-solventsB.VollmertIndividualcellstructuremodel,close-packedstructureofindividualchainsP.H.LindenmeyerHighlycoiledorirregularlyfoldedconformationalmodel,limitedchaininterpenetrationT.G.F.SchoonPearlnecklacemodelofsphericalstructuralunitsV.A.KarginBundlemodel,aggregatesofmoleculesexistinparallelalignmentW.PechholdMeandermodel,withdefectivebundlestructure,withmeander-likefoldsG.S.Y.YehFolded-chainfringed-micellargrainmodel.Containstwoelements:grain(ordered)domainofquasi-parallelchains,andintergrainregionofrandomlypackedchainsV.P.PrivalkoY.S.LipatovConformationhavingfoldedstructureswithRgequalingtheunperturbeddimensionR.HosemannParacrystallinemodelwithdisorderwithinthelamellaeS.A.ArzhakovFoldedfibrilmodel,withfoldedchainsperpendiculartofibrillaraxisModelsoftheamorphousstateinpictorialform無定型高分子模型圖示Modelsincreaseindegreeoforderfrom(a)to(d).Flory'srandomcoilmodel無規(guī)線團PrivalkoandLipatov'srandomlyfoldedchainconformations無規(guī)折疊鏈Yeh'sfolded-chainfringed-micellargrainmodel兩相球粒Pechhold'smeandermodel回紋波EvidencesforrandomcoilmodelAbsenceofanomalouseffectsforrubberelasticmodulusandstress-temperatureparameterwhendiluentisadded.Whenradiateamorphouspolymerinbulkandsolution,thecrosslinkingdegreeissimilar.Thegyrationradiusinbulkandsolutionissimilar(bySAXSandSANS)EvidencesforfringedmicellargrainmodelForrandomcoil:a/c<0.65,inpractice:a/c0.85-0.96.Orderedstackingispreparativeforfastcrystallization.Afterthermaltreatment,densityandsizeofmicellesincreases.Whiteningupontensileforrubber.2.4Orientationalstate取向態(tài)結構2.4.1OrientationPhenomena

取向現(xiàn)象Preferredarrangementofpolymerchain,segmentorcrystallinedomainunderexternalforceinsomespecificdirections(分子鏈、鏈段、晶粒等在外力作用下沿特定方向作占優(yōu)勢的排列)AspecialphenomenainpolymericmaterialsOrientationstate——one-ortwo-dimensionalorderCrystallinestate——three-dimensionalorderprocessingfilm(biaxialdrawingorblowing)fiber(drawing)pipesandrods(injection)amorphousorientatedamorphouscrystallineun-orientatedcrystallineorientated聚合物的取向一般有兩種方式：單軸取向(uniaxialorientation)：在一個軸向上施以外力，使分子鏈沿一個方向取向。如纖維紡絲再如薄膜的單軸拉伸雙軸取向(biaxialorientation)：一般在兩個垂直方向施加外力。如薄膜雙軸拉伸，使分子鏈取向平行薄膜平面的任意方向。在薄膜平面的各方向的性能相近，但薄膜平面與平面之間易剝離。薄膜的雙軸拉伸取向2.4.2OrientationMechanism

取向機理鏈段取向整鏈取向球晶取向與變形晶區(qū)取向與重組可在高彈態(tài)實現(xiàn)只能在粘流態(tài)實現(xiàn)取向單元無定形聚合物Amorphouspolymer晶態(tài)聚合物Crystallinepolymer鏈段取向非晶區(qū)Amorphousregion晶區(qū)Crystalregion鏈段取向球晶變形，晶片傾斜、滑移、取向取向與解取向問題聚合物可以取向，但取向是一種熱力學不穩(wěn)定狀態(tài)，在一定的外力、時間、溫度下又有解取向。整鏈取向整鏈取向為了維持取向狀態(tài)，獲得取向材料，必須在取向后迅速使溫度降低到玻璃化溫度以下，使分子和鏈段“凍結”起來，這種“凍結”仍然是熱力學非平衡態(tài)。只有相對穩(wěn)定性，時間長了，溫度升高或被溶劑溶脹時，仍然有發(fā)生自發(fā)的解取向性。

取向快，解取向也快，所以鏈段解取向比分子鏈解取向先發(fā)生。熱水中洗衣服發(fā)生縮水、變皺的現(xiàn)象纖維的熱定型工藝2.4.3MethodstoDeterminetheDegreeofOrientation

取向度的測量方法取向（程）度的表示拉伸比——拉伸前后長度之比取向函數(shù)Fθ為分子鏈主鏈與取向方向間的夾角理想單軸取向：θ=0cosθ=1F=1完全無規(guī)取向：F=0Soundvelocitymethod聲速法Wide-angleX-raydiffraction廣角X射線衍射法Birefringenceanisotropicmethod雙折射法InfraredDichroism紅外二向色性測量方法WAXD取向參數(shù)(A:半峰寬)沿圓周方向積分Question:Can1DWAXDbeusedtodeterminecrystallinityoforientatedpolymersamples?沿半徑方向積分聲速法原理：聲速沿分子鏈的傳播速度>>鏈間的傳播速度聲波在完全未取向聚合物中的傳播速度待測聚合物取向方向上的傳播速度Birefringenceanisotropicmethod

雙折射法2.4.4InfluenceofOrientationtotheProperties取向對性能的影響Tensileratio20g/cm3xc%n20g/denier%TgC11.338330.006811.8450712.771.3694220.106123.555723.561.3804400.128843.027854.491.3841430.142064.5789Polyesterfiber*

取向方向的拉伸強度顯著提高*材料呈現(xiàn)各向異性的特性*熱穩(wěn)定性能得到相應提高2.5Liquidcrystalstate液晶態(tài)結構2.5.1液晶的化學結構與分類不論高分子還是小分子液晶，形成有序流體都必須具備一定條件，從結構上講，稱其為液晶基元液晶基元包括棒狀(條狀)、盤狀或雙親性分子棒狀(或條狀)長徑比大于4盤狀軸徑比小于1/4雙親性分子有特殊的相互作用力MBBA2.5nm0.5nm5CB2nm近晶相C近晶相A向列相2.5.2Categoryofliquidcrystal液晶種類近晶相C近晶相A向列相膽甾相按液晶基元所在位置分類主鏈型液晶側鏈型液晶按液晶形成條件分類熱致液晶：通過加熱而形成液晶態(tài)的物質

共聚酯，聚芳酯Xydar,Vector,Rodrum溶致液晶：在某一溫度下，因加入溶劑而呈現(xiàn)液晶態(tài)的物質

核酸，蛋白質，芳族聚酰胺PBT,PPTA(Kevlar)和聚芳雜環(huán)PBZT,PBO感應液晶：外場（力，電，磁，光等）作用下進入液晶態(tài)的物質PEunderhighpressure流致液晶：通過施加流動場而形成液晶態(tài)的物質聚對苯二甲酰對氨基苯甲酰肼結構液晶包括高分子液晶和小分子液晶。不論高分子還是小分子，形成有序流體都必須具備一定條件，從結構上講，稱其為液晶基元。液晶基元棒狀(或條狀)長徑比大于4雙親性分子盤狀軸比小于1/4分類按液晶核的排列分按液晶基元所在位置分按液晶的形成條件分棒狀盤狀向列相N：只有方向序無位置序近晶A相SA：有位置序和方向序近晶C相SC：有位置序和方向序且既有層面的法向方向又有晶核的共分方向柱相向列相(DiscoticN)DN有序程度SC>SA>N如果層內間隔相等Dho如果層內間隔不等Dhd主鏈液晶主側鏈液晶側鏈液晶熱致液晶：液晶物質加熱熔融形成的液晶。溶致液晶：液晶物質溶于溶劑所得到的液晶。HighrigidityRod-likechainStronginteractionKevlar/芳綸14Kevlar49/芳綸14142.5.3Propertiesandapplicationofliquidcrystalpolymers

液晶高分子的性能和應用Propertiesofsomefibers

一些纖維的性能MaterialTensilestrengthMPaYoung’smodulusGPaElongationatbreak%Densityg/cm3Kevlar49fiber28001272.51.44UHMWPEfiber30001000.94Polyesterfiber11001414.51.38Carbonfiber35302301.51.76Carbonwhisker210001000SiCfiber30002201.42.55Glassfiber2500703.52.55Steelfiber18002042.07.83c*各向同性液晶cT*各向同性液晶T液晶紡絲在高于形成各向同性溶液的濃度下、低于形成各向同性溶液的溫度下對液晶溶液進行紡絲。液晶原位增強聚合液晶顯示LCD-Liquidcrystaldisplay液晶紡絲：在低牽伸倍數(shù)下獲得高度取向、高性能纖維液晶的應用CrystallinestateAmorphousstateOrientationstateLiquidcrystallinestate三維有序，熱力學穩(wěn)定宏觀無規(guī)線團，局部可能有序一維或二維有序，由外力誘導，熱力學不穩(wěn)定取向單元可以是鏈段，整鏈或晶粒一維或二維有序，熱力學穩(wěn)定取向單元是液晶基元2.6StructureofponentPolymers多組分聚合物的結構2.6.1Conceptofponentpolymers多組分聚合物的概念Definition含兩種或兩種以上高分子鏈的復合體系，其中一種或幾種主要性能明顯優(yōu)于單一組分NomenclatureponentPolymers多組分聚合物Multi-phasePolymers多相聚合物PolymerBlend高分子共混物PolymerAlloy高分子合金Whyponentpolymers？

為什么要發(fā)展多組分聚合物Relativelyfewnewpolymerswillbeintroducedcommerciallyinthefuturebecauseofunfavorableeconomics：RequiresnewmonomersRequireschangeincurrentpolymersynthesisprocessRequirescompliancewithgovernmentpre-manufacturingregulationsRequiresyearsbeforeprofitabilityPotentialadvantagesofblendingknownpolymerstoproducenewproductsLowercostofdevelopmentandlowercapitalinvestmentShortenedtimefortestingandapprovalwhenworkfromknownpropertydatabaseofblendedpolymersBlendpreparationmaybedoneinextrusionequipmentPotentialforuseofrecycledpolymersSomecommercialpolymerblends2.6.2Categoryofponentpolymers多組分聚合物的品種Blend物理共混物熔融共混、溶液共混Blockcopolymer嵌段共聚物活性陰離子聚合Graftcopolymer接枝共聚物自由基聚合InterpenetratedPolymerNetwork互貫聚合物網絡分別聚合高分子材料均聚物聚合物基復合材料共混物共聚物交替共聚物接枝共聚物嵌段共聚物無規(guī)共聚物熔融共混物膠乳共混物溶液共混物互穿聚合物網絡多組分聚合物兩種單體并不形成各自的鏈段均相結構兩組分相容單相連續(xù)結構一相為連續(xù)相，形成基體（matrix）一相為分散相，為顆粒狀（domain）、棒狀、蜂窩狀等微區(qū)兩相連續(xù)結構兩相連續(xù)并互相貫穿，多見于IPN兩相互鎖結構兩相互相交錯，但均沒有貫穿整個體系2.6.3Structureofponentpolymers多組分聚合物的結構ABSMultiphase嵌段共聚