简介：Thinfilmsofpolymerblendscomposedofalternatingcopolymer,diblockcopolymerand/orhomopolymerarestudiedusingMonteCarlosimulation.Amultilayermorphologyisobservedinthefilm,thatis,theblendedpolymersassembleintoindividualdomainsarrangedfrominteriortothesurfacesofthefilm.Thecoexistingcomponentsresidingthroughouttheneighboringdomainsinthefilmmakenodistinguishableinterfacebetweenanyneighboringdomains.Bythismeans,itformsaverticalcompositiongradientinthepolymericfilm.Beingdifferentfromlayer-by-layerdepositionofpolyelectrolyteorhydrogenbondingapproachetc.,thelayeredstructureinthisstudyisformedbypolymerblendinginonestep.Alternatingcopolymersarefoundtobeessentialcomponentstoformverticalcompositiongradient(layeredstructure)inthinfilms.

简介：Basedonthepreparativeexperimentsofthelight-emittingdiode(LED)encapsulant,threetypesofmonomermodelswithdifferentfunctionalgroupsarecarriedouttostudythepolymerizationprocessbydynamicMonteCarlo(DMC)simulationandbondfluctuationmodel(BFM).Wecalculatethedegreeofpolymerization,theradiusofgyrationandthefrequencyofvoidspherestodiscussthepolymerizationprocess,themolecularsizeandthespatialdistributionatdifferentvolumefractionsandproportions.OurresultsareinagreementwithGrest'sdecayrateandFlory'sscalelaw.Simulationsshowthatthepolymerizationprocessdependsontheappropriatevolumefractionandproportionexceedingly,andthevolumecontractioninthepolymerizationprocesscanalsobeobservedinthisstudy.Theseinvestigationscouldprovidesomeinsightsintotheunderstandingofthepolymerizationprocessoftheencapsulantandhelpustoadjusttheparametersinlaterexperiments.

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简介：Theconformationalanddynamicpropertiesofpolypropylene(PP)forbothpuremeltsandblendswithdifferentchaintacticitywereinvestigatedbyMonteCarlosimulationofisotactic(iPP),atactic(aPP)andsyndiotactic(sPP)polypropylenes.Thesimulationofcoarse-grainedPPmodelswasperformedonahighcoordinationlatticeincorporatingshort-andlong-rangeintramolecularinteractionsfromtherotationalisomericstate(RIS)modelandLennard-Jones(LJ)potentialfunctionofpropanepairs,respectively.ThedynamicsofchainsinbinaryPP/PPmixturewereinvestigatedwiththecompositionofC150H302withdifferentchaintaciticity.ThediffusionratesofPPwithdifferentstereochemistryaregenerallyintheorderas:iPP>aPP>>sPP.ForPP/PPblendswith50:50wt%binarymixtures,immiscibilitywasobservedwhensPPwasintroducedintothemixtures.ThediffusionrateofiPPandaPPbecamesloweraftermixing,whilesPPdiffusessignificantlyfasterinthebinarymixtures.ThemobilityofPPchainsdependsonbothintramolecular(molecularsizeandchainstiffness)andintermolecular(chainpacking)interactions.TheeffectofintramolecularcontributionisgreaterthanthatofintermolecularcontributionforiPPandaPPchainsinbinarymixtures.ForsPPchain,intermolecularinteractionhasgreaterinfluenceonthedynamicsthanintramolecularcontribution.