微相分離在高分子科學(xué)的應(yīng)用進展

微相分離在高分子科學(xué)的應(yīng)用進展第1頁，課件共23頁，創(chuàng)作于2023年2月Outline1.ConceptsofMetastablestates2.Metastablestatesinsingle-componentsystem3.Metastablestatesinpolymerblendsystem4.Metastablestatesinpolymer-solvent-nonsolventsystem5.Conclusion第2頁，課件共23頁，創(chuàng)作于2023年2月Equilibriumandstabilityinclassicalmechanics(A)anunstableequilibrium;(B)astableequilibrium;(C)arandomequilibrium;and(D)adouble-well,whichincludesoneunstableequilibriumpointsurroundedbytwostableequilibriumpoints.Twofilleddotsrepresentthelimitofstability.1.ConceptsofMetastablestates第3頁，課件共23頁，創(chuàng)作于2023年2月Stableequilibriumandmetastability

MetastablestateG<F>EquilibriumstateAsametastablestate,itisstablewithrespecttoinfinitelysmallperturbations,butitmaynotbestablewithrespecttolimitedperturbations(overcomethefreeenergybarrier⊿G)towardsastableequilibriumstate.G第4頁，課件共23頁，創(chuàng)作于2023年2月Atransformationfromonestablestatetoanotherstablestatewillproceedthroughsuccessivestagesofmetastablephaseswheneversuchametastablestateexists.Phenomenologically,ametastablestatemayexistduetoitsfastkineticpathwayeventhroughthisstateisthermodynamicallylessstablethantheequilibriumstate.OstwaldStephenZ.D.ChengCondensedstatesinpolymericmaterials:includingtransitionthermodynamics,kinetics,molecularmotioninmetastablestates,crystalstructureandmorphology,liquidcrystalpolymers第5頁，課件共23頁，創(chuàng)作于2023年2月2.Metastablestatesinsingle-componentsystemPEO:NIFIFtransition

Cheng,S.Z.D.et,al.Macromolecule,,1997,29:311–327.第6頁，課件共23頁，創(chuàng)作于2023年2月Gibbs–Thomson:第7頁，課件共23頁，創(chuàng)作于2023年2月StephenZ.D.Cheng,2007,448:1006-1008..PE:crystalstylestransition

C.H.M.Weber,et.al.NanoLett.,2007,7(7):2024-2029第8頁，課件共23頁，創(chuàng)作于2023年2月EnantiotropicandmonotropicphasebehaviorsEnantiotropicPhaseBehaviorMonotropicPhaseBehaviorGTdTiMeltL.C.CrystalGTiTmMeltL.C.Crystal第9頁，課件共23頁，創(chuàng)作于2023年2月OneexampleofmonotropicbehaviorinpolymersTangetal.Chem.Mater.,Vol.13,No.1,2001HOBT-C8

DSCcoolingcurvesofHOBT-C8

DSCheatingcurves

第10頁，課件共23頁，創(chuàng)作于2023年2月SinglePhaseIdealequilibriumtwomacroscopicphasesInpracticalcasedispersionphase(Metastablephase)3.Metastablestatesinpolymerblendsystem0DGQ*QB1B2XB2XB1MiscibleMixtureofAandB

第11頁，課件共23頁，創(chuàng)作于2023年2月DG0B1B2XB2XB1S1S2PhaseseparatedmixtureofAandBBinodalSpinodalTwoPhaseMetastableRegionUCSTphasediagram第12頁，課件共23頁，創(chuàng)作于2023年2月One-stepphaseseparation

Two-stepphaseseparation

Z.Wangetal.Polymer，2005，46：2675–2684

X.H.

Zhang,etal.Macromolecules,Vol.39,No.21,2006第13頁，課件共23頁，創(chuàng)作于2023年2月?BP:

Berghman’sPoint

?AtBP,phaseatconcentratedsideofthe

linevitrifies.?TgT

BP

ConcentrationofPolymer

Tg

becomesindependentofconcentration,andphasemorphologyisfrozenin.Liquid-liquidphaseseparation withvitrification第14頁，課件共23頁，創(chuàng)作于2023年2月Liquid–liquidphaseseparation

withcrystallizationCrystallizationTmTConcentrationofPolymerC*A*B*ABM2M1M3M4InvariantLinePhasemorphologyofM1:Phase+crystalmorphologyofM3:第15頁，課件共23頁，創(chuàng)作于2023年2月Oneexampleofliquid-liquidphase separationwithcrystallizationX.H.Zhang.et,al.RapidCommun.2005,26,1285Fluctuation-AssistedCrystallization第16頁，課件共23頁，創(chuàng)作于2023年2月schematicallydiagramofliquid-liquidofpolymer-solvent-nosovent4.Metastablestatesinpolymer-solvent-nonsolvent第17頁，課件共23頁，創(chuàng)作于2023年2月Thecompositionpathschematicallydiagramofthetopofcastingfilmduringtheimmersionprecipitationprocess.C.-Y.Kuoetal./JournalofMembraneScience315(2008)187–194第18頁，課件共23頁，創(chuàng)作于2023年2月(a)PhasediagramofBuOH/DCM/PLLA.(b)ProcessofporousfibersformationZ.Qietal./MaterialsLetters,(2008),inpress第19頁，課件共23頁，創(chuàng)作于2023年2月進一步凝固Ｈ２０Ｈ２０Ｈ２０Ｈ２０Ｈ２０Ｈ２０ＤＭＳＯ＋Ｈ２ＯＤＭＳＯ＋Ｈ２ＯＤＭＳＯ＋Ｈ２ＯＤＭＳＯ＋Ｈ２ＯＤＭＳＯ＋Ｈ２Ｏ國內(nèi)外碳纖維質(zhì)量的差異不是完全凝膠化第20頁，課件共23頁，創(chuàng)作于2023年2月H20

H20H20H20

H20●H20●

H20●真正凝膠化第21頁，課件共23頁，創(chuàng)作于2023年2月Transientstatesinpolymerphasetransformations;Identificationsofphaseinpolymercrystalpolymorphism;Monotropicliquidcrystallinepolymers;