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简介：Poly(ethyleneterephthalate)(dacron,PET)filmswereexposedunderargonplasmaglowdischargewithdifferentglowsandinducedpolymerizationofacrylicacid(AA)inordertointroducecarboxylicacidgroupontoPET(PET-AA)assistedbyultravioletradiation(UV).HirudinimmobilizedPET(PET-HRD)filmswerepreparedbythegraftingofPET-AA,followedbychemicalreactionwithhirudin.ThesurfacestructureofthetreatedPETwasdeterminedbyX-rayphotoelectronspectroscopy(XPS).Thewettability,surfacefreeenergy,andinterfacefreeenergyofthefilmswereinvestigatedbycontactanglemeasurement.Thebloodcompatibilityofthefilmswasassessedbyplatelet-adhesiontestandfibrinogenconformationalchangemeasurementstoevaluatetheviabilityofthematerialsinbiomedicalengineering.Measurementbyscanningelectronmicroscopy(SEM)revealedthattheamountsofadhered,aggregatedandmorphologicallychangedplateletswerereducedonthehirudin-immobilizedPETfilms.Enzyme-linked-immunoassaymeasurementsthatdisclosedfibrinogenconformationalchangesshowedresultsconsistentwiththeplatelets’behavior.

简介：Uniaxialtensiletestingatstrainratesrangingfrom10-3to10-1s-1wascarriedouttostudytherate-dependentme-chanicalbehaviorforpoly(ethyleneterephthalate)(PET)usedinthepackagingindustry.Theexperimentalresultsshowthatarate-dependentplasticbehaviorexistsforPETmaterial.Thevalueoftheyieldstrengthwasfoundtoincreasewiththeincreasingstrainrate.AnewconstitutivemodelbasedontheimprovedCowper-Symondsrate-dependentconstitutivemodelisproposedtodescribethemechanicalbehaviorofPETmaterialinthestrainraterangingfrom10-3to10-1s-1,providingmoreaccuratematerialdataforthesubsequentsimulationanalysisofdroptestanddynamicbuckling.ThepredictionsobtainedusingtheproposedmodelarecomparedwithexperimentalresultsoftheimprovedCowper-Symondsmodel.Thesimulatingresultsoftheproposedmodelagreewellwiththeexperimentaldata.Foralowstrainrate,thepredictionsofthismodelaremoreprecisethanthoseobtainedusingtheimprovedCowper-Symondsmodel.Thisconfirmsthatthenewconstitutivemodelissuitablefordescribingtheme-chanicalbehaviorofPETmaterialatalowstrainrateandmodelingimpactproblem.

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简介：Inthispaper,thedispersionandnucleationbehaviorofultrafineparticlesofsilicaandlayeredsilicate(LS)inpoly(ethyleneterephthalate)(PET)matrixareinvestigatedandcharacterizedbyTransmissionElectronMicroscopy(TEM),WideAngleX-rayDiffraction(WAXD),DynamicScanningCalorimetry(DSC),andAtomicForceMicroscopy(AFM).ThesolidprecursorsbasedonsilicaandLSaresuggestedoriginallyforpreparingnanocompositeswithgooddispersionmorphology.Resultsshowthattheinitialsub-micron(1000～500nm)LSparticlesareexfoliatedordispersedintonanometer-scaleparticles(30～70nm)duringtheirpolymerizationwithPETmonomers.Thesedispersednanoparticlesformanorderedmorphologyintheirnucleationandgrowthduringannealingnanocomposites.DSCpatternsrevealthatthedoublemeltingpeaksofannealedPET-LSnanocompositesdisappear,whiletheyhaveshrunkeninPET-silicaones.ThesefindingsstronglydemonstratethatthedispersednanoparticlesacceleratethecrystallizationofPET.ThedispersedLSparticleshavehigherpercolationandnucleationperformancethanthoseofsilica.Thehomogeneousdistributionmorphologyofultrafineparticlesiseasilyobtainedbycontrollingtheloadoftheircorrespondingprecursors.SuchadispersionobviouslyimprovesPETpropertiesinthatitsheatdistortiontemperature(HDT)increasesfrom76℃to103℃,andcrystallizationincreases2～4timesmorethanthatofPET.Especially,thenanocompositefilmskeepthemselvestransparentwhenparticleloadiswithin2wt.%thoughthereare3wt.%orsoofagglomeratedparticlesinthenanocomposites.

简介：Thethermallystimulatedshapememorybehaviorofethyleneoxide-butyleneterephthalate(EOBT)segmentedcopolymerswithdifferentsoftsegmentmolecularweightandhardsegmentcontentwasinvestigated.ThedeformationrecoveryratioR_foftheEOBTsamplesincreaseswiththesoftsegmentmolecularweightandthehardsegmentweightcontent,whiletheaverageoveralldeformationrecoveryspeedV_rincreaseswiththehardsegmentcontent.Thetemperatureofmaximumdeformationrecoveryspeed(T_M)isdeterminedbythemeltingtemperatureofthesoftsegmentcrystalsandthestabilityofthecrystallizedhardsegmentdomains.

简介：Thedigitalimageprocessingtechniquewasusedfortheextractionofphysicalinformationfromthetemporalimageofphasestructureintheprocessofphaseseparationintheblendofpoly(butyleneterephthalate-co-caprolactone)withpolycarbonate.Thepowerspectrumimagesofthetwo-dimensionalFouriertransformation(2DFT)ofthetemporalimageofphasestructurereflectthechangeofthephasesizewithtime.

简介：ThermotropicliquidcrystallineVHEterpolyestersmadefromvanillicacid(V),p-hydroxybenzoicacid(H)andpoly(ethyleneterephthalate)(E)werestudiedby400MHzNMRspectra,wideangleX-raydiffraction,scanningelectronandpolarizingmicroscopes.ItwasfoundthattheVHEterpolyestershadrandomsequencedistribution.TheVHEterpolyesterfilmsexhibitedhighlyorientedfibrillarstructure.

简介：Theisotropyoranisotropyinsomephysicalpropertiesoftheammorphouspoly(ethyleneterephthalate)filmsuniaxiallydrawnattemperaturesaboveitsT_gandthenquenchedtoroomtemperaturehavebeenstudied.Experimentalresultsherepresentedshowthatthisamorphousstateofhighglobalchainorientationbutnearlyrandomsegmentalorientation,theGOLRstate,isnearlyisotropicinrefractiveindicesandYoung’smodulusforsmalldeformation,whileitisveryprobablyanisotropicinthermalconductionandmicrowavedielectricproperties.

简介：DyeingofPETmaterialsbytraditionalmethodspresentsseveralproblems.Plasmatechnologyhasreceivedenormousattentionasasolutionfortheenvironmentalproblemsrelatedwithtextilesurfacemodifications,andtherehasbeenarapiddevelopmentandcommercializationofplasmatechnologyoverthepastdecade.Inthiswork,thesynergisticeffectofatmosphericpressureplasmaonalkalineetchinganddeepcoloringofdyeingpropertiesonpolyethyleneterephthalate(PET)fabricsandfilmswasinvestigated.ThetopographicalchangesofthePETsurfacewereinvestigatedbyatomicforcemicroscopy(AFM)images,whichrevealedasmoothsurfacemorphologyoftheuntreatedsamplewhereasahighsurfaceroughnessfortheplasmaand/oralkalinetreatedsamples.TheeffectsofatmosphericpressureplasmaonalkalineetchingofthestructureandpropertiesofPETwereinvestigatedbymeansofdifferentialscanningcalorimetry(DSC),themainobjectiveofperformingDSCwastoinvestigatetheeffectoftheplasmapre-treatmentontheT_gandT_m.UsingatensilestrengthtesterYG065HandfollowingastandardprocedurethemaximumforceandelongationatmaximumforceofPETmaterialswasinvestigated.Oxygenandargonplasmapre-treatmentwasfoundtoincreasethePETfabricweightlossrate.ThecolorstrengthofPETfabricswasincreasedbyvariousplasmapre-treatmenttimes.ThepenetrationofplasmaandalkalinereactivespeciesdeepintothePETstructureresultsinbetterdyeabilityandleavesasignificanteffectontheK/Svaluesoftheplasmapre-treatedPET.Itindicatedthatplasmapre-treatmenthasagreatsynergisticeffectwiththealkalinetreatmentofPET.

简介：One-stepreactioncompatibilizedmicrofibrillarreinforcediPP/PETblends(CMRB)weresuccessfullypreparedthrougha'slitextrusion-hotstretching-quenching'process.CrystallizationbehaviorandmorphologyofCMRBweresystematicallyinvestigated.Scanningelectronicmicroscopy(SEM)observationsshowedblurryinterfaceofcompatibilizedcommonblend(CCB).ThecrystallizationbehaviorofneatiPP,CCB,microfibrillarreinforcediPP/PETblend(MRB)andCMRBwasinvestigatedbydifferentialscanningcalorimetry(DSC)andpolarizedopticalmicroscopy(POM).TheincreaseofcrystallizationtemperatureandcrystallizationrateduringnonisothermalcrystallizationprocessindicatedbothPETparticlesandmicrofibrilscouldserveasnucleatingagentsandPETmicrofibrilsexhibitedhigherheterogeneousnucleationability,whichwerealsovividlyrevealedbyresultsofPOM.ComparedwithMRBsample,CMRBsamplehaslowercrystallizationtemperatureduetoexistenceofPETmicrofibrilswithsmalleraspectratioandwiderdistribution.Inaddition,sinceinsitucompatibilizertendstostayintheinterphase,itcouldalsohinderthediffusionofiPPmoleculestothesurfaceofPETphase,leadingtodecreaseofcrystallizationrate.Two-dimensionalwide-angleX-raydiffraction(2D-WAXD)waspreformedtocharacterizethecrystallinestructureofthesamplesbyinjectionmolding,anditwasfoundthatwell-developedPETmicrofibrilscontainedinMRBsamplepromotedformationofβ-phaseofiPP.