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

简介：Thecopolymerizationofp-diethynylbenzene（PDEB）withphenylacetylene（PhA）,4,4’-diethynylbiphenyl（DEBP）orm-diethynylbenzene（MDEB）arestudiedbyvaryingmoleratiosofmonomers.WhenthemoleratiosofPDEB/PhAarelessorequalto1/5,thecopolymersaresolubleandfusible,buttheothercopolymersareinsolubleandinfusible.Theresultsshowthatthegoodsolventofcross-linkedcopolymersisbenzeneandtheirsolubilityparameteris9.15cal0.5.cm（-1.5）.Andtheirswellability（θp）,Hugginsparameter（χ）,density(d425)andtheaveragemolecularweightsbetweencrosslinks（c）aremeasured.Itisfoundthatθpandcofcopolymersaregreaterbutd425islessthanthatofrespectivehomopolymers.IRspectrashowthatthecopolymershavetransoidconfigurationandsmallnumberofunreactedethynylgroupsexistinthecopolymers.Themechanismaboutthepolymerizationoracetylenicderivativesinitiatedby（Ph3P）2PdCl2isdiscussed.

简介：PPV－basedcopolymerswithcyanogroupinthemainchainhavebeensynthesizedbyWittig-typepolycondensationofalkoxy-substituteddialdehydesand4,4'-bis(cyanomethyl)-substituteddiphenylether:[-C6H4-O-C6H4-C(CN)=CH-C6H2(OR)2-C=C(CN)-]n(POPPV),Thecopolymersarehighlysolubleincommonsolventsandtheirsuperhighlytransparenthomogeneousthinfilmscanbeformedbyspincoatingdirectlywithoutheattreatment.ThechemicalstructuresaredeterminedbyNMRandIRspectroscopysandevaluatedusingphotoluminescence,gel-permeationchromatography(GPC)andDSC(orTGA)methods.TheincorporationofethergroupintothePPVbackbonehasaninterruptionofthemain-chainconjugation,thatresultsintheblue-shiftofelectroluminescencespectraandenhancemntthesolubility.

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简介：Acetylcrosslinkedpolystyrene(EPS)andcrosslinkedbromoacetylpolystyrene(BEPS)beadsweresynthesizedbyFridel-Craftsacetylationofpolystyrene(PS)andbrominationofEPSrespectively.FTIR,XPS,andTG-TDGwereemployedtocharacterizetheirstructures.TheresultsrevealedtherearetwotypesofbromineintheBEPSmolecule.Oneisinthemainchainofpolystyreneandtheotherisintheacetyl.TheresultsofTG-DTGshowedthattheratesoflossweightofPS,EPS,andBEPSwere92.7%,92.2%,and81.3%amongthe300℃～500℃;7.3%,7.8%,and18.7%in594℃,660℃,and584.8℃,respectively.

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简介：X-rayphotoelectronspectroscopy(XPS)wasadoptedtoelucidatesorptionmechanismofphenolandp-nitrophenolontoaweaklyanionexchangerD301.ThedistributionofspecificformsoftertiaryaminogrouponD301wasobtainedandeffectoffreetertiaryaminogrouponphenolsorptionontoD301wasdiscussed.TheresultindicatedthatthepercentoftheprotonatedtertiaryaminegrouponpolymericmatrixwasmuchlowerthanthereferencecompoundN,N-dimethylbenzylamineatanidenticalpHvalueinsolutionduetothemuchloweractivitydegreeofhydrogenionininnerresinphasethanintheexternalsolution.LessfreeaminogrouponD301resultsinlesssorptioncapacityofphenolandp-nitrophenolinanacidicsolution.UndertheexperimentalconditionsbothphenolsorptionontoD301canbeexplainedassolidextractionandthedistributioncoefficientvarieslinearlywiththecontentoffreeaminogrouponD301.

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

简介：Acomparisonoftheadsorptionofbenzoicacidandp-nitrobenzoicacidonthenewhypercrosslinkedpolymericadsorbentAM-I,withthatbymacroporousAmberliteXAD-4,includingtheequilibriumadsorptionisotherms,thedynamicadsorptionbehaviorsthroughcolumnandtheadsorptionthermodynamicswerestudied.ResultsshowthatFreundlichequationgivesafittingadsorptionisotherm.ThespecificsurfaceofAM-lisonly67%ofthatofAmberliteXAD-4,buttheadsorptioncapacitiesonAM-1aremuchhigherabout125%～166%thanthatonAmberliteXAD-4,whichiscontributedtothemicroporemechanismandpolarity.Thenegativevaluesoftheadsorptionenthalpyareindicativeofanexothermicprocess.Enthalpyandfreeenergychangesofadsorptionbothmanifestaphysic-sorptionprocess.Thenegativevaluesoftheadsorptionentropyindicatethattheadsorptioniswellconsistentwiththerestrictedmobilitiesandtheconfigurationsoftheadsorbedbenzoicacidmoleculesonthesurfaceofstudiedadsorbentswithsuperficialheterogeneity.Bothadsorbentswereusedinmini-columnexperimentsforadsorbingbenzoicacidexpectingtoelucidatethehigherbreakthroughadsorptioncapacityofthenewhypercrosslinkedpolymericadsorbentAM-1ascomparedwiththatofAmberliteXAD-4.

简介：Fluorescencepropertiesofaseriesofstyrene/p-divinylbenzene(St/p-DVB)copolymerbeadswereinvestigatedbysteady-statefluorescencespectra.Inadditiontothefluorescenceofthephenylringexcimer,anewemissionbandatca395nmappearswhenp-DVBcontentinfeedishigherthan13%(wt).Theintensityofthisnewemissionwasfoundtochangewithp-DVBcontentandtodecreasewithswollenbeads.Theoriginofthisnewemissionisconsideredtobeamulti-ringexcimerformation.

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.

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