简介:Apolymer(poly(9,10-anthracenevinylene-alt-4,4’-(9,9-bis(4-(4’-(1,2,2’-triphenylvinyl)phenoxy)butyl)-9Hfluorene-2,7-diyl)dibenzaldehyde),P1)wassuccessfullysynthesizedthroughtheWittig-Hornerreactionbyemployingfluoreneand9,10-distyrylanthracenemoietiesasbuildingblocksforbackboneandtetraphenylethenesaspendantgroups.Photophysicalandthermalpropertiesoftheresultingpolymericemitterwerefullycharacterizedbyultraviolet-visible(UVVis)absorptionandphotoluminescence(PL)spectra,thermogravimetricanalysis(TGA)anddifferentialscanningcalorimetry(DSC).WhileP1emitsanorange-lightcenteredat567nmindilutetetrahydrofuran(THF)solution,thesolidpowderofthepolymerexhibitsstrongyellowemissionpeakedat541nm.Itisalsofoundthattheas-synthesizedpolymershowsuniquepropertyofaggregation-enhancedemission(AEE).Inaddition,P1possesseshighthermalstabilitywithadecompositiontemperature(Td,5%)of430°Candhighmorphologicalstabilitywithaglasstransitiontemperature(Tg)of171°C.Underthestimulusofmechanicalforce,theemissionofP1canbechangedfromyellowtored(Δλmax=61nm),showingaremarkablemechanochromism.TheresultsfromXRDanalysissuggestthatsuchmechanochromicphenomenonofP1isprobablycausedbythedestructionofcrystallinestructure,whichleadstotheconformationalplanarizationofthedistyrylanthracenemoietiesformingbythepolymerizationandtheincreaseofmolecularconjugationofthebackbone.
简介:TheA-Bblockcopolymerof0634-chloroethylglycidyletherwithstyrenecanbegotbytheeasymethodofone-steppolymerization.ThestructureofA-Bblockcopolymerwasconfirmedbytheelementaryanalysis,turbiditytitration,molecularweightmeasurement,IR-spectra,13C-NMR,1H-NMRandDTAinvestigationoftheproducts.Also,theeffectsofsolvents,reactiontimeandtemperatureonthecomposition,Mnandyieldofcopolymerhavebeenstudied.
简介:Immobilizedtriazinedyeaffinitychromatographyhasbeenwidelyusedforproteinpurification.Inthispaper,CibacronBlueF3G-4wasimmobilized,throughaspacerarm,ontoarigidhydroplhilicporouspolymerbyreactinganepoxy-group-containingpoly(vinylalcohol)with6-aminohexyl-N'-CibacronBlueF3G-A,whichwasobtainedbyreactingCibacronBlueF3G-4withexcessof1,6-diaminohexane,inapH8.6buffer,Theepoxy-group-containingpoly(vinylalcohol)waspreparedbytreatingmacroporouspoly(vinylalcohol)withexcessepichlorohydrininthepresenceofNaOHindimethylsulfoxide.Themacroporouspoly(vinylalcohol)waspreparedbyhydrolysisofmacroporouscrosslinkedpoly(vinylacetate),whichwassynthesizedbysuspensioncopolymerizationofvinylacetateandtriallylisocyanurateinthepresenceofbutylacetateandn-heptaneasdiluents.TheCibacronBlueF3G-A-immobilizedpoly(vinylalcohol)waspackedinastainlesssteelcolumn(250×5mmI.D.)andthechromatographicbehaviorsofseveralproteins(cytochromec,lysozyme,bovineserumalbumin,insulin,andlactatedehydrogenase)weredetermined.
简介:Averymildandextremelyefficienthydrolysismethodfortransformationofpolystyrene-b-poly(tert-butylacrylate)(PS-b-PtBA)topolystyrene-b-poly(acrylicacid)(PS-b-PAA)wasdesignedandcarriedoutusingmoreconvenientandinexpensivechlorotrimethylsilane/sodiumiodideasreagents.Thehydrolysisproductcanself-assembleinaqueousmediatogiveregularmicelleswithPSblockformingthecoreandPAL4blockformingthecorona,orintetrahydrofuran(THF)togivereversemicelleswiththehydrophilicblockinthecore.
简介:Inthiswork,DSCandSEMstudiesindicatethation-ligandinteractioncanbeutilizedtoenhancetheinteractionofpoly(styrene-block-2-vinylpyridine)[P(S-b-2VP)]andpolyethylenebasedionomer(Surlyn).Thecompatibilityforthisblendingsystemcanbeimprovedbythisspecialinteractionand20/80wtistheoptimumblendingcompositionwithgoodcompatibility.FTIRresultsfurthercertifythatstronginteractionsexistintheblendingsystem.
简介:Thehybridstructuresofpolystyrene-b-poly(ethyleneoxide)(PS-b-PEO)blockcopolymerandinorganicnanoparticleswithgoodstabilityandbiocompatibilityhavepotentialapplicationsindrugdeliveryandbioimaging.Sphericalco-assembliesofPS120-b-PEO318andoleylamine-cappedCdSquantumdots(QDs)areproducedsuccessfullyinthisworkbyaddingwatertoamixedcommonsolvent,suchasN,N-dimethylmethanamide(DMF)/chloroform,DMF/tetrahydrofuran(THF),orDMF/toluene.TheenergydispersiveX-ray(EDX)spectrumindicatesthatQDsarelocatedattheinterfacebetweenthecoreandshellofthesphericalco-assemblies.Theco-assemblyprocessduringwateradditionistracedbytransmissionelectronmicroscopy(TEM)andturbiditymeasurement.Sphericalco-assembliesareformedthroughbuddingfrombilayersoftheblockcopolymerandQDs.Themorphologyoftheco-assembliesisrelatedtothemiscibilityoftheQD-dispersingsolventswithwaterandthemorphologychangesfromasphericaltoavesicle-likestructurewithDMF/toluene.IncreasingTHFcontentinthemixedsolventcausesmorphologicaltransitionsfromsphericalco-assembliestomulti-branchedcylindersandmicelleswhereQDsarelocatedinthecentralcore.Increasingchloroformcontentyieldsvesicle-likestructureswithprotrudingrodsonthesurface.Themechanismofthemorphologicaltransitionsisalsodiscussedindetail.
简介:指向nano探查基于的一个可被细菌破坏的肿瘤poly(?-caprolactone)-b-poly(ethylene乙二醇)有磁性的回声成像(MRI)的块共聚物(PCL-b-PEG)micellefunctionalized对比代理人diethylenetriaminepentaacetic酸金轧(DTPA-Gd3+)在壳上并且一在红外线附近(NIR)在为磁性的回声和光双形式的成像的核心的染料是准备。纵的relaxivity(r1)PCL-b-PEGDTPA-Gd3+,micelle是13.4(mmol/L)?1s?1,DTPA-Gd3+的三褶层,并且比有类似的结构的许多聚合对比代理人的高。在里面忍受xenografted胸肿瘤的一只裸体老鼠的光成像显示出的vivo双形式的micelle优先地经由folic在肿瘤积累了由提高的渗透和保留(EPR)效果的调停酸的活跃指向和被动累积。结果显示dualmodalitymicelle是为癌症察觉和诊断的有希望的nano探查。
简介:Lamellarcrystalsofdiblock,triblockandfour-armpoly(ethyleneglycol)-b-poly(ε-caprolactone)(PEG-b-PCL)crystalline-crystallinecopolymersweresuccessfullyobtainedfromtheirsolution.Morphologyandstructureoflamellarcrystalsofcrystalline-crystallinecopolymerswereinvestigatedusingtapping-modeatomicforcemicroscopy(AFM)andselectedareaelectrondiffraction(SAED).Allofthesesamplesshowedthetruncated-lozengemultilayerbasalshapeswithcentralscrewdislocationorcentralstack,whichwereallobtainedsimultaneouslyfromtheoilbath.ThediffractionpatternofPEGblocklamellarcrystalisattributedtothe(120)diffractingplanesandthepatternofPCLblocklamellarcrystalisattributedtothe(110)diffractingplanesand(200)diffractingplanesaccordingtotheSAEDresults.Four(110)crystalgrowthplanesandtwo(200)crystalgrowthplanesarediscoveredforthePCLblocks,butthe(120)crystalgrowthplanesofPEGblocksarehidedinthefigureofAFM.Thecrystallinestructureofthefour-armcopolymers(FA)ismoredisorderandconfusedthanthatofthediblock(DI)copolymerandthestriatedfoldsurfacestructuresoflamellarcrystalsoffour-armcopolymers(FA)aresmootherthantheseoflinearanalogues,owingtotheconfusedcrystallizationofblockscausedbythemutualrestrictionofblocksandthehindranceofthedendriticcores.Inaddition,theaspectratioofFAisgreaterthanthatoftheothers.Itishypothesizedthattherearetworeasonsforthechangeofaspectratios.First,the(200)diffractingplanesofPCLcrystalsgrewslowlycomparedtotheir(110)diffractingplanesbecauseofdifferenceintheenergybarrier.Secondly,edgedislocationsonthe(200)diffractingplanesarealsoresponsibleforthevariationoftheaspectratio.Consequently,thecrystallinedefectsareaugmentedbythecompetingblockscrystallizedsimultaneouslyandthehindranceofthedendriticcores.
简介:Thediblockcopolymersintercalatedlayeredsilicatewaspreparedviaameltdispersiontechnique.Thentheeffectofintercalatedhybridasfilleronacrylonitrile-butadiene-styreneresinwascharacterizedbyX-raydiffraction,transmissionelectronmicroscopy,stress-strainmeasurementsinelongation.