简介：3-Ethynyl-4-（trimethylsilyl）thiophene（1a）and3-ethynyl-4-bromothiophene（1b）selectivelyundergoacetylenepolymerizationsinthepresenceoftheMoCl5-andWCl6-Ph3SiHcatalyststogivesoluble,high-molecular-weightpoly（thienylacetylenes）（2）（Mwupto602000）inhighyields（upto100%）.LighttransmissionspectraofTHFsolutionsof2continuouslyred-shiftwithincreasingconcentration.Theconcentratochromismshowsalogarithmicconcentrationdependence;thatis,theopticaltransitionsof2arepredictablytunablebysimplychangingtheirconcentrations.

简介：Aryloxy-terminatedpolydimethylsiloxanes(AOS)weresynthesizedbythetelomerizationofhexamethylcyclotrisiloxane(D3)withphenols.ThestructuresofAOSwerecharacterizedbyUV,IR,^2HNMRandelementalanalysis,Theeffectsofthereactionconditionsandthemoleratiosofthereactantsonthemolecularweightofthepolymerwerediscussed.AOS′sstructuralinfluenceonbactericidalaction,flocculationandhydrolysiswasstudied.

简介：LighttransmissionspectraofTHFsolutionsofpoly(C60-co-methylmethacrylate)sandpoly(C60-co-styrene)scontinuouslyred-shiftwithincreasingconcentration.Formationoffullerenenanoclustersmayberesponsiblefortheunusualspectralshiftwithconcentration.Ithaslongbeenscientists’dreamto'tune'material’spropertiesbysimplemeans,andtheC60-containingpolymersrepresentsuchagroupofnovelmaterialswhoseopticalpropertiesarepredictablyandreversiblytunablebyasimplechangeinconcentration.

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简介：Synthesis,structures,propertiesandapplicationsofhypercrosslinkedpolystyrenesarereviewedwith50refereneces.

简介：Theeffectofdifferentkindsofcomonomerswithorwithoutflexiblechainonproper-tiesofcopolyesters,suchastransitiontemperature,crystallizationvelocity,crystallinityandsizeofcrystallites,isstudied.Theexperimentalresultsindicatetheobviousdiffer-enceinpropertiesbetweencomonomerswithiso-andortho-structureofphenylringandcomonomerswithflexiblechain.Theinfluenceofchemicalstructureofcomonomersonpropertiesofcopolyestersisdiscussed.

简介：Throughinterfacialpoly-condensationofR2SnCl2(R=Me,Bu)withvariousdiacids,diphenols(diols),diamines,amino-acids,hydroxyacids,urea,orthiourea,aseriesoforgano-tinpoly-esters,poly-ethers,poly-amines,poly-amine-esters,poly-ureas,poly-thioureaswereprepared,andcharacterisedaltogethertotalling100polymers,amongwhich91arepreviouslyunreported.ThesynthesizedpolymershaveapotentialasathermostabilizerinPVCproducts.

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简介：Electricalconductionbehaviorofpristineandiodinedopedpolyetherimides(PEI)hasbeeninvestigatedunderbothtransientandsteadystateconditionsintheoperatingtemperaturerange50-200℃atvariouselectricfieldsof12-60kV/cm.Thetransientcurrentsshowthehyperbolicdecaycharacter,andthedecayexponentp(ameasureofcurrentdecayrate)decreaseswithtemperature(7)anddopingconcentration.Theoriginoftransientcurrentshasbeenattributedtothedipolarnatureofcarbonyl((?)C=O)groupsandtheetherlinkagespresentinthemainchainofPEI.Thelowfieldsteadystateconductionisohmicinnature.Themagnitudesofionicjumpdistance(a)valuesdonotfavoranionictypeofconductionasapossibleconductionmechanisminpristineaswellasiodinedopedPEI.TheSchottkycoefficientsestimationsdonotshowthepossibilityofSchottkytypeorPoole-Frenkeltypeconductionmechanismsinthelowtemperatureregion(<120℃),however,inthehightemperatureregion(>120℃)thereisacertainpossibilityofPoole-Frenkeltypeconductionmechanisminbothpristineandiodinedopedsamples.Thedualslopeinthe1gIversus1/Tcurvesforiodinedopedsamplesindicatesthepresenceofmorethanonetypeoftrappinglevels.

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简介：Thisworkisfocusedonsimulatingtherheologicaleffectsinpolyamide.Anexperimentalstudyiscarriedoutinordertoassesssuchfeaturesofpolyamideas:thehystereticbehavior,thestrainratedependence,andthestressrelaxation.Thematerialresponseintensionisinvestigated.Digitalimagescorrelationmethod(DIC)isemployedinordertomeasurethematerialcompressibility.Anewlydevelopedconstitutivemodel,whichwaspreviouslyusedtosimulatethemechanicalresponseofpolyethylenesubjectedtomoderatestrainsandcompressiveloadings,isappliedtocapturethelargestrain,inelasticbehaviorofpolyamideintension.Thegatheredexperimentaldataareutilizedtodeterminethevaluesofconstitutiveconstantsofviscoelasticityandplasticity,whichdescribetherheologicalpropertiesofpolyamide.Thedeterminedmaterialparametersareincludedinthetext.Differentstrategiesforevaluatingthematerialparametersarediscussed.Theproposedconstitutiveequationisimplementedintothefiniteelement(FE)system,ABAQUS,bytakingadvantageoftheusersubroutineUMAT,whichallowstodefinecustommateriallaws.SomeexemplaryFEsimulationsthatwereusedtoinvestigatetheperformanceofthedevelopedsubroutinearedescribed.

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简介：ThispaperintroducedthesynthesisandpropertiesofIERbasedon2-hydroxyethylmethacrylate.ThederivativescontainingDEAE-,CM-,SO3Hgroupswerepreparedandtheirusesinbiochemistrywerestudies.

简介：Bis(β-alkoxycarbonylalkyl)tindichlorideswereinterfacialcondensedwithorganicdithio-alcoholstogiveaseriesofneworgano-tinpolymers.Experimentalparameterswerediscussed.Thepolymerssynthesizedweretestedfortheireffectontheheat-stabilizationofPVCresins.Theresultsareofinterestinthisareaofapplication.

简介：Fivenovelnear-infraredelectrochromicaromaticpolyimides(PIs)withpendentbenzimidazolegroupweresynthesizedfrom4,4’-diamino-4’’-(1-benzylbenzimidazol-2-yl)triphenylamine(namedasDBBT)withfivedifferentdianhydridesviatwo-steppolymerizationprocess,respectively.ThemaximumUV-VisabsorptionbandsofthesePIslocateatabout335nmforsolidfilmsduetotheπ-π*transitions.Areversiblepairofdistinctredoxpeaks,thatwereassociatedwithanoticeablecolorchangefromoriginalyellowtoblue,wasobservedinthecyclicvoltammetry(CV)test.Anewabsorptionpeakemergedat847nminnear-infrared(NIR)regionwithincreasingvoltageinUV-Vis-NIRspectrum,whichindicatesthatPIcanbeusedasNIRelectrochromicmaterial.ThesenovelPIshavegoodelectrochemicalstability,appropriateenergylevelsforthehighestoccupiedmolecularorbital(HOMO)andthelowestunoccupiedmolecularorbital(LUMO),intherangeof-5.17eVto-5.20eVand-2.14eVto-2.26eV(versusthevacuumlevel)determinedbycyclicvoltammetrymethod.Thesevaluesbasicallyconsistedwiththeresultsofquantumchemicalcalculation.Thesepolyimidescanbeusedasnovelelectrochromicandholetransportationmaterials.

简介：Usingcarboxymethylchitosan(CM-CTS)assnakeresin,B-62resincrosslinkedbytriethylentetraamine(TETA)ascageresin,aseriesofnovelsnake-cagetyperesinweresynthesized.Suchfactorsasthebestsyntheticconditions,theswellingandregenerationproperties.andthesorptioncapactitiesoftheabovementionedresinsformetalionswereinvestigated.Theexperimentalresultsshowtheseresinshavegoodswellingpropertiesandmechanicalstability,anddonotrunoffinorganicandinorganicsolvents.ThesorptioncapactitiesofthemforCu^2+,Ni^2+,Zn^2+,andPb^2+were0.89,0.54,0.32,and0.22mmol/g,rspectively.

简介：Thestraininducedcrystallizationbehaviourinpolyimidefrom1,4-bis(3’,4’-dicarboxyphenoxy)benzeneand4,4’-oxydianiline(PEI-E)hasbeeninvestigatedbyWAXD,DSCandFTIR.TheresultsobtainedshowthatcrystallizationinPEI-Edidtakeplacejustaftertensileyielding.Meanwhile,theeffectofstraininducedcrystallizationonthethermomechanicalpropertieswasstudiedbyDMAandTMA,theresultsofwhichindicatethatthecrystallizationandhotstretchinghaveacertaininfluenceonthedynamicmechanicalproperties,suchasweakeningtheβrelaxationanddecreasingtheglasstransitiontemperature.TheTMAresultsconfirmtheshiftingofglasstransitiontemperaturetolowertemperatureregionafterhotstretching.ThisphenomenoncouldbewellexplainedbytheeffectofresidualstressaccordingtoEyring’stheory.