简介：Carbazole-basedbi-functionalphotorefractivepolyacrylateswerepreparedviafreeradicalpolymerizationandpost-azo-couplingreaction.ThestructureofpolymerswascharacterizedbyFouriertransforminfraredspectroscopy(FTIR)andprotonnuclearmagneticresonance(1H-NMR)spectroscopy.Thedifferentialscanningcalorimetry(DSC)andthethermalgravimetricanalysis(TGA)wereusedtocharacterizethethermalpropertyofpolymers.Theresultsindicatethatthoughtheglasstransitiontemperature(Tg)ofpolymersincreaseswithincreasingtheratioofNLOgroups,thepolymerswithdifferentratiosofNLOgroupsstillallshowlowglasstransitiontemperaturesaround60°C,andgoodthermalstability,whicharefavorabletothepracticalapplicationofthesepolymers.Thegelpermeationchromatographic(GPC)resultindicatesthatthesepolymersallhavehigh-molecular-weightwhichisfavorabletothelongtermstabilityofthematerial.Further,thesepolymershavegoodsolubilityinchloroformsolvent,andthesolutionscaneasilybefabricatedintoopticallytransparentfilms.Gaincoefficientsof75cm-1,185cm-1and66cm-1canbeobservedatzeroexternalelectricfieldwithoutanyadditionagentorpre-polingforpolymersP-2,P-3andP-4respectively.ThedifferentcontentsofNLOgroupsresultinthedifferentpropertiesofpolymersP-2,P-3andP-4.

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简介：Thestructureofpolyimidefrom1,4-bis(3’,4’-dicarboxyphenoxy)benzeneand4,4’-oxydianilinefilmspecimensbeforeandafterhotstretchinghasbeeninvestigatedbyWAXD,DSCandFTIR.AsevidencedbyboththeWAXDandDSCresults,itcouldbebelievedthatstraininducedcrystallizationdidtakeplaceafterhotstretching.Meanwhile,shiftingpositionandsplittingofsomebandpeaksexistedontheFTIRspectrogramswereexplainedintermsoftheclosepackingofchainsandthechangesofinter-molecularcharge-transferinteractionbetweenimidegroupsandaromaticgroupsuponcrystallization.

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简介：ThepreparationofconductingPPQfilmwasfirstreportedinthepreviouspaper.Itisveryinterestingthatthisfilmishighlysensitivetomoistureinair.ThehydrationanddehydrationofthefilmareaccompaniedbychangenotonlyincolorbutalsoinconductivityandUV-visiblespectrum.TheconductingPPQisreducedtoPPQandlosesitsconductivityafterbeingsoakedinwater.

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简介：Poly（β-carboxyethylmethylsiloxane）-LiClO4andpoly（β-alkoxylethylmethylsiloxane）-LiClO4crosslinkedfllmshavebeenprepared.Theionicconductivityofthefilmsdependsonthepolymerspecies,concentrationoflithiumperchlorate,temperatureandcontentofcrosslinkingagent.Theeffectofhighpolarorganicsolvent1,4-butyrolactoneontheionicconductivityandmechanicalpropertiesofpoly（β-carhoxyethylmethylsiloxane）-LiClO4systemwasalsoinvestignied.

简介：Ionicconductivityvaluesforsegmentedpolyetherpolyurethaneurea（PEUU）complexeswithLiClO4weredeterminedandvaluesashighas～1.1×10-4S·cm-1at353Kand～1.0×10-5S·cm-1at306Kwereachieved.TheionicconductivitydatawereanalyzedusingtheVTF（Vogel-Tamman-Fulcher）equationandWLF（Williams-Landel-Ferry）typeequation.Valueshavebeenestimatedforthe"apparent"activationenergiesofiontransportfromVTFequationandtheylieintherange2.70—5.53kJ·mol-1.

简介：Threepolymericadsorbentswithhydrogenbondingacceptors,methylamine,N-methyl-acetamideandaminotri(hydroxymethyl)methanemodifiedresinsaresynthesizedfromchloromethylatedX-5resin.AdsorptionisothermsofphenolandtheophyllineontothethreemodifiedresinsandtheoriginalX-5resinfromaqueoussolutionaremeasured.TheresultsshowthatadsorptionofcompoundswithhydrogenbondingdonorontomethylamineandN-methylacetamidemodifiedresinsisenhancedascomparedwiththatontoX-5resin,andadsorptionmechanismbetweentheadsorbentsandtheadsorbatesismainlybasedonhydrogenbondingandhydrophobicinteraction.Whileadsorptionofcompoundswithhydrogenbondingdonorontoaminotri(hydroxymethyl)methanemodifiedresinisloweredascomparedwiththatontoX-5resin,andadsorptionmechanismbetweentheadsorbentandtheadsorbatesismainlybasedonhydrophobicinteraction.

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简介：Thiscontributionreportsethylenepolymerizationbehavioroftitaniumcomplexesincorporatingbis(phenoxyimine)ligands.Sixphenoxy-imineTi(IV)complexes{6-R1-2-[CH=N(2,6-difluoro-3,5-diR2-4-R3Ph)]C6H3O}2TiCl2(1:R1=H,R2=H,R3=H;2:R1=H,R2=H,R3=4-vinylphenyl;3:R1=CH3,R2=H,R3=H;4:R1=CH3,R2=H,R3=4-vinylphenyl;5:R1=CH3,R2=F,R3=H;6:R1=CH3,R2=F,R3=4-vinylphenyl)havebeensynthesizedandevaluatedforethylenepolymerizationusingdriedMAO(simplifiedasDMAO)ascocatalyst.AnobviouscatalyticheterogeneityofCat2(Complex2/DMAO)towardsethylenepolymerizationwasobserved,whichwasillustratedbydecreasedactivity,multimodalmolecularweightdistributionandpartiallyimprovedparticlemorphologycomparingwithCat1.Moreover,Cat3exhibits'living'characteristicsintheprocessundercertainconditions(25°C,lessthan20min).Otherwise,themoderatetohighethylenepolymerizationactivityofca.105-106gPE/(molTi·h)andhighmolecularweight(Mw=105-106)ofpolyethylenecanbeobtainedbychangingtheskeletonstructureofthesecomplexes.

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简介：Thetreatmentandresourcereuseof1,2,4-acidproducingwastewaterbyself-mademacroporousadsorptionresinND,A-107wasstudiedinthispaper.Optimumadsorptionanddesorptionprocessparameterswereacquiredbysystematicallystudy.ThepolymericresinNDA-107indicatedgoodadsorption&desorptionof1,2,4-acidinthewastewater.Theremovalefficiencyof1,2,4-acid,CODerisabout78%,72%respectively.Itisevidentthatthisadsorptionprocessisanefficienttreatmentmethodfor1,2,4-acidproducingwastewater.Atthesametime,theaccumulationandresourcereuseofl,2,4-acidcanberealizedinthisprocess.

简介：Highqualitypoly(5-cyanoindole)(P5CI)filmswereelectrosynthesizedbydirectanodicoxidationof5-cyanoindoleonstainlesssteelsheetinthemixedelectrolytesofborontrifluoridediethyletherate(BFEE)anddiethylether(EE)(byvolume1:1)+0.05molL~(-1)Bu_4NBF_4.Thefilmformedcanbepeeledofftheelectrodeintofreestandingfilms.TheadditionofEEintoBFEEcanimprovethesolubilityofmonomer.P5CIfilmsobtainedfromthismediumshowedexcellentelectrochemicalbehaviorwithconductivityof10~(-2)Scm~(-1).Structuralstudiesshowedthatthepolymerizationof5-cyanoindoleoccurredatthe2,3position.As-formedP5CIfilmswerethoroughlysolubleinstrongpolarorganicsolventdimethylsulfoxide(DMSO)whilepartlysolubleintetrahydrofuran(THF)oracetone.FluorescencespectralstudiesindicatedthatP5CIwasagoodblue-lightemitter.

简介：Polymer-supportedRCpCpTiCl2(Cp=η^5-C5H4;RCp=η^5-RC5H4)havebeenpreparedandreducedbyi-C3H7MgBrinsitu，thenusedincatalyticisomerizationof1,5-hexadiene.Theisomerizationof1,5-hexadieneleadstoamixtureofcyclicandlinearproducts.Theratioofcyclictolinearproductdependsonthenatureofthesupporterandthesubstituentonthecyclopentadienylring.Theformercontributesthemost,forexample,silicasupportedCp2TiCl2gavecyclic-linearratioof99/1,whileforpolymer-supportedCp2TiCl2species,linearcompoundsarethemajorproductsandtheratioofcyclictolinearproductchangeswithdifferentRgroupsonthecyclopentadienylring.

简介：TiCl_4/MgCl_2/claycompoundcatalystwaspreparedbychemicalreaction.Exfoliatedpolypropylene(PP)/claynanocompositesweresynthesizedbyinsitupolymerizationwiththiscompoundcatalyst.Effectsofpolymerizationtemperature,polymerizationtime,propylenepressure,solventconsumptionandpre-treattimeofcatalystoncatalystactivityandcatalyticstereospecificitywerestudied.Underoptimalconditions,activityofthenano-compoundcatalystisabout88.3kg/(molTi·h).IsotacticityofPPobtainedinthenanocompositesisintherangeof89%-99%,anditsmeltingtemperatureisabout159℃.Theweight-averagemolecularweightofPPcanreach6.7×10~5-7.8×10~5,andthemolecularweightdistributionisbetween7.7and7.9.

简介：Polyolefinsthatbearachiralsidechain(typicallyanisobutylgroup)experienceaso-calledmacromolecularamplificationofchirality:thechiralside-chaininducesaslightpreferenceforeithertgortg-mainchainconformation.Thisslightconformationalbiasisamplifiedcooperativelyalongthechain,andresultsinpreferredchiralityofthemainchainhelicalconformations.Asaresult,thesepolymersdisplayaliquid-crystal(LC)phasebothinsolutionand,inthemeltasatransientphaseonthewaytocrystallization.Theexistenceoftwoprocesses(melt-LCandLC-crystaltransitions)resultsinunconventionalbehaviorsthatwerefirstanalyzedbyPinoandcollaboratorsbackin1975.Thesepolymersalsoofferameanstotestthestructuralconsequencesofrecentlyintroducedcrystallizationschemes.Theseschemespostulatetheformationofatransientliquid-crystalphaseasageneralschemeforpolymercrystallization.