简介：阶段PVDF水晶结构和在先存在的阶段PVDF球粒以内的豌豆的结晶化上的豌豆的效果被光显微镜学OM，红外线的光谱学红外和扫描电子显微镜学SEM调查了。结果证明阶段PVDF球粒由展出高度弄弯的像滚动的形态学的lamellae组成并且在充满豌豆的混合优先地发展。与增加豌豆集中，滚动直径增加和滚动更好与对方被分开。豌豆在interspherulitic区域使第一结晶，transcrystalline层发展。随后，豌豆的transcrystalline层继续在阶段PVDF球粒以内成长，例如在在滚动之间的区域，直到在另外的豌豆transcrystalline层或球粒上侵犯。结晶化动力学结果显示在阶段PVDF的intraspherulitic区域的豌豆晶体的生长率与阶段PVDF的结晶化温度与豌豆，而是否定豌豆的内容显示出积极关联。

简介：PVDF的词法特征上的PBS的效果被光、原子的力量显微镜学在各种各样的条件下面调查了。整洁的PVDF在170戠?与非常地弱的birefringence形成大表格球粒，这被发现?M

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

简介：Ithasbeenwellknownthatfluorinatedpolyurethanesexhibituniquelylowsurfaceenergy,biocompatibilityandbiostability,thermalandoxidativestabilityandnonstickingbehavior.Consequently,thesepolymershaveattractedconsiderableinterest.However,themechanicalpropertiesoffluorinatedpolyurethanesusuallydeclinewithincreasingfluorinecontents.Theblendingoffluorinatedpolyurethaneswithnormalpolyurethanewascarriedouttoachievebalancedmechanicalandsurfaceproperties.Itwasfoundthatpolyurethanewithgoodmechanicalpropertiesandlowsurfaceenergycanbeobtainedbyaddingasmallamountoffluorinatedpolyurethane.Thefluorinatedsidechainscaneasilymigratetouppermostsurfacesoftheblendsuntillthefluorinelevelatthesurfacebecomesalmostsaturated.Ithasbeenshownfromcontactangle,XPSandAFMmeasurementsthatonlyaslittleas0.34wt%offluorinelevelisenoughtoproduceasurfacesaturatedwithfluorine,andthefluorinelevelattheuppermostsurfaceisonehundredtimeshigherthanthatintheblendbulk.Thefinaloutersurfacestructuresofthepolyurethaneblendwereindependentofthecontentofthefluorinatedpolyurethaneintheblendsduetothesurfacessaturatedbyfluorine.

简介：Anovelsmallband-gapconjugatedpolymer-poly[(3-acetylpyrrole-2,5-diyl)(4-dimethylaminobenzyliene)(3-aeetylpyrrolequinodimethane-2,5-diyl)](PAPDMABE)-anditsprecursorweresynthesizedbyasimplemethodandcharacterizedby1H-NMR,FT-IR,TGAandUV-VIS.ThepolymercanbedissolvedinstrongpolarsolventssuchasDMSO,DMForNMP.Theband-gapenergyofPAPDMABEwasfoundtobe0.95eV.Theconductivityofdopedproductswithiodinefallsintherangeofasemiconductor.``

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：Poly(4-vinylpyridine)(P4-VP)nanofiberandfluoresentpoly(4-vinylpyridine)/porphyrin(P4-VP/TPPA)nanofiberwererespectivelypreparedbyelectrospinning.TheeffectoftheconcentrationofP4-VP/dimethylformamide(DMF)electrospinningsolutionsonthemorphologyofP4-VPnanofiberwasinvestigatedanditwasfoundthattheaveragediameterofthenanofiberofP4-VP/DMFincreasedwiththeincreaseoftheconcentrationofthespinningsolution.AftertheadditionofTPPAtotheP4-VP/DMFspinningsolution,thediameterofP4-VP/TPPAnanofiberbecameevenduetotheincreaseoftheconductivityoftheP4-VP/DMF-TPPAsolution.Thephotoluminescent(PL)spectralanalysisindicatesthattheemissionpeakpositionofP4-VP/TPPAnanofiberisalmostthesameasthatofpureTPPAatabout650nmwithoutpeakshift,andwhenitwasstoredfor20days,theemissionpeakofP4-VP/TPPAnanofiberisalsoat650nm,indicatingthatthefluorescentpropertyofP4-VP/TPPAnanofiberisstable.Fourier-transforminfrared(FTIR)spectrumconfirmsthechemicalcompositionoftheresultingP4-VP/TPPAcompositenanofiber.

简介：二氧化碳共聚物聚氨酯胺PUA与聚丙烯碳酸盐PPC被混合以便没有牺牲另外的机械性质，改进PPC的坚韧和灵活性。与纯PPC相比，有装载的5wt%PUA的PPC/PUA混合证明400%在裂缝在延伸增加，虽然相应让步力量象稍微显示出的33.5MPa和幼仔模量一样仍然保持高减少。在PPC/PUA的结合的相互作用混合的分子间的氢被FTIR，2D红外和XPS系列分析，和PUA的细微地驱散的微粒结构在PPC证实在SEM图象被观察，它为PPC的韧化的机制提供了好证据。

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简介：Bilayerhumidity-responsiveactuatorsaregenerallycomposedofactuatingandsupportinglayersofdifferentmaterialswithlargelydifferentwettability.Suchkindsofbilayeractuatorssufferfromlowadhesiveforcebetweenthetwolayersduringusage.Thisstudydemonstratesthepreparationofhumidity-responsivebilayeractuatorsthathavethesamematerialsintheactuatingandsupportinglayerstoavoidtheadhesiveissue.Thebilayeractuatorsconsistofaporouspoly(acrylicacid)σAA)/poly(allylaminehydrochloride)(PAH)layerandanonporousPAA/PAHlayerthatarefabricatedbyexponentiallylayer-by-layerassemblymethod.Atahigh/lowrelativehumidity(RH),thenonporousPAAIPAHlayercanefficientlyexpand/shrinkbyabsorbing/desorbingwaterwhilethevolumeexpansion/shrinkageoftheporousPAA/PAHlayerinanenvironmentwithchangedhumidityissignificantlysuppressedbythemicrometer-sizedpores.Thelargelydifferentexpansion/shrinkageofthenonporousandporousPAA/PAHlayerswhensubjectedtohumiditychangesenablesrapidandreversiblerolling/unrollingmotionsofthebilayeractuator.Thebilayeractuatorshowsafasterrollingspeedandalargerbendingcurvaturewhensubjectedtoalargerhumidityincrease.

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简介：在这篇论文，我们为极端夸张操作员的力量构造Almansi分解。构造将以一个建设性的方法被做。

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：Inordertoimprovetheflexibilityofpoly(propylenecarbonate)(PPC),poly(1,2-propylenesuccinate)(PPSu)wasusedtoplasticizePPCinabatchmixer.TheeffectsofPPSuonthemiscibility,thermalstability,mechanicalandrheologicalpropertiesoftheblendswereinvestigated.PPCwaspartiallymisciblewithPPSu.ItwasdemonstratedthatPPSudecreasedtheglasstransitiontemperatureandmeltviscosityofPPC,asshownintheDSCandrheologicalcurves.WiththeincreaseinPPSucontent,thePPC/PPSublendsshoweddecreasedtensilestrength,however,theelongationatbreakwasincreasedto1100%forthe70/30PPC/PPSublend.TheintroductionofPPSuprovidedanefficientandnovelplasticizationmethodtoextendtheapplicationareaofPPC.

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简介：Poly（aryleneetherdiketone）swerepreparedbythearomaticnucleophilicdisplacementreactionof4,4’-difluorobenzilwithdifferentbisphenolsinthepresenceofan-hydrouspotassiumcarbonateindiphenylsulfoneatelevatedtemperature.Thepolymersobtainedhadinherentviscosityof0.51～0.63dL/g,andexhibitedglasstransitiontemper-aturerangingfrom136～217℃mainlydependingonthebisphenolsusedinthepolymersynthesis.Thermogravimetryofthesepolymersshowedexcellentthermalstability,indi-catingthat10%weightlossesofthepolymerswereobservedintherangeabove428℃and438℃inairandnitrogen,respectively.ThemechanicalpropertiesofthesepolymerswerealsodescribedandthepermeabilityoffivepolymersforH2,O2andN2wasdeterminedat30℃.

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简介：Awidevarietyofdifferenttypesofmicroorganismsareknowntoproduceintracellularenergyandcarbonstorageproducts,whichhavebeengenerallydescribedasbeingpoly(β-hydroxybutyrate),PHB,butwhichare,moreoftenthannot,copolymerscontainingdifferentalkylgroupsattheβ-position.Hence,PHBbelongstothefamilyofpoly(β-hydroxyalkanoastes),PHA,allofwhichareusuallyformedasintracellularinclusionsinbacteriaunderunbalancedgrowthconditions.Recently,itbecameofindustrialinteresttoevaluatethesePHApolyestersasnaturalbiodegradableandbiocompatibleplasticsforawiderangeofpossibleapplications,suchassurgicalsuturesorpackagingcontainers.Forindustrialapplications,thecontrolledincorporationofrepeatingunitswithdifferentchainlengthsintoaseriesofcopolymersisdesirableinordertoproducepolyesterswitharangeofmaterialpropertiesbecausephysicalandchemicalcharacteristicsdependstronglyonthepolymercomposition.Such"tailor-made"copolymerscanbeproducedundercontrolledgrowthconditionsinthat,ifadefinedmixtureofsubstratesforacertaintypeofmicroorganismsissupplied,awelldefinedandreproduciblecopolymerisformed.

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.