简介：PP/claycompositeswithdifferentdispersions,namely,exfoliateddispersion,intercalateddispersionandagglomeratesandpanicle-likedispersion,werepreparedbydirectmeltintercalationorcompounding.TheeffectofclaydispersiononthecrystallizationandmorphologyofPPwasinvestigatedviaPLM,SAXSandDSC.Experimentalresultsshowthatexfoliatedclaylayersaremuchmoreefficientthanintercalatedclayandagglomeratesofclayinservingasnucleationagentduetothenano-scaledispersionofclay,resultinginadramaticdecreaseincrystalsize(lamellarthicknessandspherulites)andanincreaseofcrystallizationtemperatureandcrystallizationrate.Ontheotherhand,adecreaseofmeltingtemperatureandcrystallinitywasalsoobservedinPP/claycompositeswithexfoliateddispersion,duetothestronginteractionbetweenPPandclay.Comparedwithexfoliatedclaylayers,theintercalatedclaylayershavealessimportanteffectonthecrystallizationandcrystalmorphology.Noeffectisseenforsampleswithagglomeratesandpanicle-likedispersion,inregardtomeltingtemperature,crystallizationtemperature,crystalthicknessandcrystallinity.

简介：TheconductivitybehaviorofAl(OH)3-acrylamidehybridpolyacrylamide(hybridPAAm)indistilledwaterwasstudied.Adiscontinuityphenomenonoftheconductivity(k)versusconcentration(c)curveofthehybridPAAminacertainconcentrationregimeisfound.ThisphenomenonisdependentonthemolecularweightofthehybridPAAmandontheparticlesizeandcontentoftheAl(OH)3colloidinthehybridPAAm.ThisphenomenonwasaccountedforassumingionizationofthehybridPAAm.

简介：Thisworkdealswiththekineticsofco-condensationpolymerizationofAB2andABmonomers,givingexpressionsofthetwo-dimensionalmolecularweightdistributionfunctionandthenumber/weightaveragemolecularweightsoftheresultingcopolymers.Thetwo-dimensionalmolecularweightdistributiondependsontwoindices,nandl,whicharetherespectivenumbersofAB2andABunitsinacopolymerspecies.Theevolutionofthetwo-dimensionalweightandzdistributionsduringtheco-condensationpolymerizationhasbeenevaluatedsystematically.Finally,thetwo-dimensionaldistributionwastransformedintoaone-dimensionalmolecularweightdistributionwithonlyonevariable(themolecularweightoftheproductsinsteadofthedegreeofpolymerization).Thecalculatedresultsshowthatthehighlybranchedcopolymerhasaverybroadmolecularweightdistributionwhentheco-condensationpolymerizationapproachescompletion.

简介：Polydimethylsiloxane(PDMS)rubberlatexwithtwosortsofsensitizers,trimethylolpropanetri-methacrylate(TMPTMA)anddiethyleneglycoldi-acrylate(DEGDA),wasirradiatedwithγ-raysandelectronbeamsinvariousconditions.TheradiationcrosslinkingreactionofPDMSoccursintheinnerphaseofthelatexandisrelativelyisolatedfromthewaterphase.Thereforetheoxygenandtheradicalsproducedbytheradiolysisreactionofwateralmosthavenoeffectonthecrosslinkingreactionofpolymer.TheexperimentaldatacorrespondwiththeCharlesby-Pinnerrelationshipinthemain.Thegelationdoses,degreeofcrosslinkinganddegradationaswellasGvaluesofcrosslinkingwerecalculated.Fromthem,thesensitizationcoefficientswerederivedtoofferaquantitativemeasurementoftheenhancingeffectofsensitizerontheradiationcrosslinking.

简介：

简介：

简介：

简介：

简介：

简介：

简介：

简介：

简介：Discussionispresentedontheuseofthephotoisomerizationofazobenzenechromophoreinthedesignandpreparationofnovelfunctionalmaterials.Thetwosystemsreviewedareazobenzenepolymer-stabilizedliquidcrystalsandazobenzeneelastomers.Inthefirstcase,apolymernetworkcontainingazobenzenemoietiesisusedtoopticallyinduceandstabilizealong-rangeliquidcrystalorientationwithouttheneedoftreatingthesurfacesofthesubstrates.Thisopticalandrubbing-freeapproachwasappliedtonematicandferroelectricliquidcrystals.Inthesecondcase,anazobenzeneside-chainliquidcrystallinepolymerisgraftedontoastyrene-butadiene-styrenetriblockcopolymertoyieldaphotoactivethermoplasticelastomer.Coupledmechanicalandopticaleffectsmakepossibletheformationofdiffractiongratingsthatmaybeusefulformechanicallytunableopticaldevices.

简介：Ourrecentstudiesconcerningthebindingofionicsurfactantsonoppositelychargedpolyelectrolytesobservedwithfluorescencetechniquesarereviewed.Thecationicsurfactantscetyltrimethylammoniumbromide(CTAB),dodecyltrimethylammoniumchloride(DTAC),andnonionicsurfactantoctaethyleneglycolmonododecylether(C12E8)wereallowedtobindonanionicpoly(2-acrylamido-2-methylpropanesulfonicacid)(PAMPS)anditspyreneand/ornaphthalenelabeledcopolymers.TherelativeexcimeremissionintensityIE/IMofacationicprobe1-pyrenemethylaminehydrochloridewerechosentomonitorthebindingprocessandtheconformationchangeofsurfactant-boundpolyelectrolytes.The1:1aggregationofpolyelectrolyte-CTABwithrespecttothechargewasfoundaslongastheCTABconcentrationwasslightlyhigherthanitscriticalaggregationconcentration(CAC).TheintermolecularNRETindicatedthattheCTAB-boundpolyelectrolytesaggregatedtogetherthroughthehydrophobicinteractionbetweentheCTABtails.However,neither1:1polyelectrolyte-DTACaggregationnorintermolecularaggregationofDTAC-boundpolyelectrolytewasobservedowingtoitsweakerhydrophobicityof12carbonatomsinthetail,whichisshorterthanthatofCTAB.Asknownfromthefluorescenceresults,nonionicsurfactantC12E8didnotbindontheanionicpolyelectrolytes,butthepresenceofPAMPSpromotedthemicelleformationforC12E8attheCACslightlybelowitscriticalmicelleconcentration(CMC).ThesolidcomplexofdansyllabeledAMPScopolymer-surfactantexhibitedadecreaseinlocalpolaritywithincreasingchargedensityofthepolyelectrolyteorwithalkanetaillengthofthesurfactant.SAXSsuggestedalamellastructurefortheAMPScopolymersurfactantsolidcomplexeswithalongperiodof3.87nmforCTABand3.04nmforDTAC,respectively.

简介：Watersolubleconductingpolyanilinewithelectricalconductivityof10-1-10-2S/cmwaspreparedemployingdopantinducedwatersolubilitytechnology.Thewaterresistanceoftheconductingfilmwassignificantlyimprovedemployingsol-gelhybridsmethod,especiallywhentheconductivepolyanilineloadingwasbelow30wt%.Thereasonfortheimprovementisthattheconductingpolyanilinechainsareconfinedinastableinorganicnetwork.

简介：Anirradiationgraftingmethodwasappliedforthemodificationofnanoparticlessothatthelattercanbeaddedtopolymericmaterialsforimprovingtheirmechanicalperformanceusingexistingcompoundingtechniques.Thefollowingitemsarediscussedinthispaper:(a)chemicalinteractionbetweenthegraftingmonomersandthenanoparticlesduringirradiation,(b)propertiesincludingmodulus,yieldstrength,impactstrengthandfracturetoughnessoftheresultantcomposites,and(c)possiblemorphologicalchangesinducedbytheadditionofnanoparticles.Throughirradiationgraftingpolymerization,nanoparticleagglomeratesturnintoanano-compositemicrostructure(comprisedofthenanoparticlesandthegrafted,homopolymerizedsecondarypolymer),whichinturnbuildsupastronginterfacialinteractionwiththesurrounding,primarypolymericmatrixduringthesubsequentmixingprocedure.Duetothefactthatdifferentgraftingpolymersbroughtaboutdifferentnanoparticle/matrixinterfacialfeatures,microstructuresandpropertiesoftheultimatecompositescouldthusbetailored.Itwasfoundthatthereinforcingandtougheningeffectsofthenanoparticlesonthepolymermatrixcanbefullybroughtintoplayataratherlowfillerloadingincomparisontoconventionalparticulatefilledcomposites.

简介：Thediblockcopolymersintercalatedlayeredsilicatewaspreparedviaameltdispersiontechnique.Thentheeffectofintercalatedhybridasfilleronacrylonitrile-butadiene-styreneresinwascharacterizedbyX-raydiffraction,transmissionelectronmicroscopy,stress-strainmeasurementsinelongation.

简介：Bythereactionofpoly(bromoacetylstyrene)(EBPS)withthiaurea(TU),akindofnovelchelatingresinwithheterocyaclicringofsulfurandnitrogen,poly[4-(2-amino)thiazoleyl-4-vinylben=ene],wassynthesized.ItsstructurewascharacterizedbyFTIRandelementalanalysis.Thefactorswhichhaveinfluenceonthereactionsuchasreactiontime,solvents,andmolarratioofreactantswereinvestigated.

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.

简介：ThecatalyticreactionofNOwithCOanddecompositionofNOovermetalmodifiedACFswereinvestigatedandcomparedwithothercarrierssupportedcatalysts.ItisdemonstratedthatPd/ACFandPd/Cu/ACFhavehighcatalyticactivityforthereactionofNO/CO,whilePt/ACF.Pt/Cu/ACFandCo/Cu/ACFhaveveryIowcatalyticactivityinsimilarcircumstance.Pd-modifiedACFpossesseshighcatalyticdecompositionofNOat300℃.Pd/CBandPd/GACpresentgoodcatalyticdecompositionabilityforNOonlyatlowflowrate.Pd/G,Pd/ZMSandPd/Ahowever,donotshowanycatalyticactivityforNOdecompositionevenat400℃.Catalytictemperature,NOflowrateandloadingofmetalcomponentsaffectthedecompositionrateofNO.ThecoexistenceofCuwithPdonCu/Pd/ACFleadstocrystallineofpalladiumtomoreunperfectedsoastothatincreasethecatalyticactivity.