学科分类
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24 个结果
  • 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℃.

  • 标签: Poly(arylene ETHER diketone) Thermal BEHAVIOR High-temperature
  • 简介:Bythereactionofpoly(bromoacetylstyrene)(EBPS)withthiaurea(TU),akindofnovelchelatingresinwithheterocyaclicringofsulfurandnitrogen,poly[4-(2-amino)thiazoleyl-4-vinylben=ene],wassynthesized.ItsstructurewascharacterizedbyFTIRandelementalanalysis.Thefactorswhichhaveinfluenceonthereactionsuchasreactiontime,solvents,andmolarratioofreactantswereinvestigated.

  • 标签: 合成 螯合树脂 含硫含氮杂环化合物 | 反应时间
  • 简介:Inthispaper,MPt/C(M=La,Nd)catalystsofPEMFCweresynthesizedbymicrowaveradiationprocess.ThecrystallinityandstructureofcatalystswererespectivelyanalyzedbyXRDandnitrogenadsorptiontests.Theactivityofcatalystswasinvestigatedbyelectrochemistryexperiment.Theresultsshowedthat:1)comparedwithPt/Ccatalystpreparedbytypicalimpregnation-reductionprocess,thesizeofMPt/CcatalystparticledecreasedandtheavailablecrystalforO2reductionincreased;2)theMPt/CcatalystshadrelativelyhighBETsurfaceareas;and3)thesecrystaltransformationsoftheMPt/Ccatalystbroughthightheelectrocatalyticactivity,andasaresult,improvedthepowerofPEMFC.

  • 标签: 合成 微波辐射 聚合物电解质膜燃料电池 催化剂 X射线衍射 氮吸附试验
  • 简介:小说芳香脂肪族(amide-imide)poly,在方面链在主要的链和氢氧根benzamide单位包含chiral单位的s从3,5-diamino-N-(4-hydroxyphenyl)的步生长聚合被获得了有不同chiral二酸氯化物(1a1e)的benzamide(2)。理论计算借助于计算化学方法被做叙述在反应下面的每二酸氯化物单体的稳定的符合构造和取向调节。这些聚合物被常规技术描绘。产生聚合物显示出好热稳定性。包括crystallinity,固有的粘性和词法特征的聚合物的另外的物理性质也被学习。

  • 标签: 纳米结构 光学活性 生产性能 世代 苯甲酰胺 羟基苯基
  • 简介:一系列新包含硅(p-arylenevinylene)poly,有在主要的链的蒽单位的s(PAV)被hydrosilylation反应综合。有机硅单位的介绍改进了聚合物的溶解度,并且-聚合的链的变化形式被打断。这些聚合物在答案在0.280.30的范围在447499nm和量收益与他们的荧光最大值作为蓝绿色的轻emitters表现了。

  • 标签: 反应合成 硅氢化 乙炔 光物理 高分子链 光发射器
  • 简介:我们在场这里周期的oligo(乙烯adipate)的第一合成经由有乙烯乙二醇的adipoyl氯化物的伪高度冲淡冷凝作用反应的s(COEA),和合成相应poly(乙烯adipate)(豌豆)经由COEA的melt聚合。COEA的结构被1H-NMR和MALDI-TOF团大小。器官的底,反应温度和到COEA的收益上的乙烯乙二醇的adipoyl氯化物的比率的效果被学习,并且最佳反应条件被揭示。豌豆,二酸和diol基于半水晶的绿脂肪族的聚酯,被COEA的melt聚合用Ti综合(n-C4H9O)是的4是的催化剂和1,10-decanediol在200点的开始者在上到葡萄牙的语言的BPI在巴西说瞄准它的以后的用法在癌症病人生活测量疼痛的紧张和干扰。方法:BPI-B从原来的位/英寸被开发,用背翻译和委员会评论。背Translatio?

  • 标签: 二酸乙二醇酯 聚合合成 熔融聚合 POLY 环状 脂肪族聚酯
  • 简介:Electrostaticlayer-by-layerself-assemblymultilayerfilmsweresuccessfullyfabricatedfromC60-ethylenediamineadduct(C60-EDA)andDNA.Undervisiblelightirradiation,DNAisreadytobecleavedandthefilmsaredestroyed.

  • 标签: Self-assembly Photo-induced cleavage DNA C60
  • 简介:Ithasbeenwellknownthatfluorinatedpolyurethanesexhibituniquelylowsurfaceenergy,biocompatibilityandbiostability,thermalandoxidativestabilityandnonstickingbehavior.Consequently,thesepolymershaveattractedconsiderableinterest.However,themechanicalpropertiesoffluorinatedpolyurethanesusuallydeclinewithincreasingfluorinecontents.Theblendingoffluorinatedpolyurethaneswithnormalpolyurethanewascarriedouttoachievebalancedmechanicalandsurfaceproperties.Itwasfoundthatpolyurethanewithgoodmechanicalpropertiesandlowsurfaceenergycanbeobtainedbyaddingasmallamountoffluorinatedpolyurethane.Thefluorinatedsidechainscaneasilymigratetouppermostsurfacesoftheblendsuntillthefluorinelevelatthesurfacebecomesalmostsaturated.Ithasbeenshownfromcontactangle,XPSandAFMmeasurementsthatonlyaslittleas0.34wt%offluorinelevelisenoughtoproduceasurfacesaturatedwithfluorine,andthefluorinelevelattheuppermostsurfaceisonehundredtimeshigherthanthatintheblendbulk.Thefinaloutersurfacestructuresofthepolyurethaneblendwereindependentofthecontentofthefluorinatedpolyurethaneintheblendsduetothesurfacessaturatedbyfluorine.

  • 标签: Polyurethane FLUORINATED polyurethane Blend Surface structure
  • 简介:Inthispaper,anewthin-layerion-exchangeresinphaseanalyticalmethodisintroduced.Itisbasedonthat,thebismuthouscationcanassociatewithiodicanions,soastoformedananioncomplex[BiI4-_]inastrongacidicenvironments.Thisanioncomplexcanalsoexchangeswithaweakeranionsonthesurfaceactivesiteofanionexchangeresin,sothata[R+][Bil4-]solidphasebinaryassociationalsystemisproduced.Owingtothesolidsystemisagreatmanydispersiveparticulates,itcanbepressedtoathin-layerbypresstoolsofthesocalled"thin-layerresinphase"or"resinphase",andusingthissolidassociationsystemspectrophotometryforthedeterminationoftracemetals.Soitcanincreasetheanalyticalsensitivity.Thisassociationsystemexhibitsmaximumabsorbanceat460nm,andobeysBeer'slawovertheconcentrationrange0.0lug/ml-l.20ug/mlofbismuthous(lll),hhasamolarabsorptivityof7.1×l^5[L/mol.cm].itindicatedtheresinphasespectrophotometryisasensitiveanalyticalmethodfortracebismuthous.Itis18timeshigherthanroutineaqueousspectrophotometry.Therelativestandarddeviationsis1.82%(n=6)fortheFfmeasurementsof0.Sug/mlBi(llO.ThedetectionlimitofBismuthous(lll)is1.4XlO~mol/L.ThemethodhasappliedtotheanalysisBi(lll)inenvironmentalwatersamples.

  • 标签: 痕量铋(III) 薄层树脂 分光光度测定法 测量 离子交换树脂 分析方法
  • 简介:为综合的一条non-isocyanate线路有优秀热、机械的性质的热塑的聚氨酯被描述。与四个聚乙烯乙二醇木钉融化1,6-bishydroxyethyloxy羰基aminohexane的transurethanepolycondensation,即PEG400,PEG600,PEG1000,或PEG1500,在不同臼齿的比率被进行。有长木钉序列的一系列热塑的polyetherurethanesTPEU被准备。TPEU经由胶化浸透层析被描绘,FTIR,<啜class=“a-plus-plus”>1H-NMR,微分扫描热量测定,thermogravimetric分析,散布的宽角度的X光检查,和张力的测试。TPEU展览T<潜水艇class=“a-plus-plus”>在12.4汦灡之间的g?

  • 标签: 热塑性聚氨酯 合成路线 异氰酸酯 序列 PEG400 凝胶渗透色谱法
  • 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.

  • 标签: 结晶化 聚烯烃 聚甲基丙烯酸甲脂 液晶相
  • 简介:PolysaccharidecoatedPLAnanoparticlesbearingaldehydegroupswerepreparedbydialysisofDMSOsolutionofcholesterolhydrophobic-modifieddextranpolyaldehydeandPLAagainstwater.Theaveragediameterofthenanoparticleswasabout160nm,andthesizedistributionwasnearlyhomogenous.ThenanoparticleswerefunctionalizedsimultaneouslywithCD71andEGFRantibodythroughtheSchiff'sbasereaction,andthenradiolabeledwith~(99m)Tc.Afterperfusedtheradiolabelednanoparticlesintotumor-bearing...

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  • 简介:Linearpolysiloxaneswithpendantbenzo-15-crown-5moietieshavebeensynthesizedfrom3′-or4′-allylbenzo-15-C-5viahydrosilylationofmethyldichlorosilane,followedbypolycondensationwithsilanol-terminatedpolydimethylsiloxane.Itwasfoundthatthepolysiloxanescouldbeusedascarriersinbulkliquidmembranetotransportions.Factorsinfluencingtransportratehavebeeninvestigated.

  • 标签: 合成 线性聚硅氧烷 苯并-15-冠醚-5 液膜
  • 简介:Ourobjectivesweretodevelopanewchemicalmethodforthepolymerizationofpyrrole.CuCl2dissolvedinC2H5OHsolventisprimarilyusedfortheinitiationpolymerizationofpyrrole.ThepolymerswithdifferentyieldandconductivitywereobtainedbyraringtheinitialconcentrationofCu2+.TheinitialconcentrationsofCu2+variedfrom1.2×10-4moleto6.48×10-3moleCu2+with2.16×10-2molepyrrole.Thepolypyrroleobtainedwascharacterizedwithelementalanalyzer,XPS,IRspectroscopy,Four-pointprobeandSEM.

  • 标签: CuCl2-C2H5OH initiation SYSTEM Polymerization of PYRROLE
  • 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.

  • 标签: p-Diethynylbenzene PHENYLACETYLENE 4 4’-Diethynylbiphenyl m-diethynylbenzene