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℃.
简介:Bythereactionofpoly(bromoacetylstyrene)(EBPS)withthiaurea(TU),akindofnovelchelatingresinwithheterocyaclicringofsulfurandnitrogen,poly[4-(2-amino)thiazoleyl-4-vinylben=ene],wassynthesized.ItsstructurewascharacterizedbyFTIRandelementalanalysis.Thefactorswhichhaveinfluenceonthereactionsuchasreactiontime,solvents,andmolarratioofreactantswereinvestigated.
简介:Theeffectsofinterfacialmodifieronthemechanicalpropertiesofkaolin-filledpolyamide6(PA6)havebeenstudied.Theinterracialinteractionbetweenpolyamide6andkaolinhasbeencharacterizedbymeansofinfraredspectroscopy(IR)andscanningelectronmicroscopy(SEM).TheresultsshowthattheroleoftheinterracialmodifierliesinforminganelasticinterlayerwithgoodadhesionbetweenkaolinandPA6.Acompositewithhighimpactstrength,hightensilestrengthandhighelasticmoduluscanbeobtainedbyinsertingtheelasticinterfacialmodifierintotherigid-particle-filledpolymersystem.
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?
简介:Ithasbeenwellknownthatfluorinatedpolyurethanesexhibituniquelylowsurfaceenergy,biocompatibilityandbiostability,thermalandoxidativestabilityandnonstickingbehavior.Consequently,thesepolymershaveattractedconsiderableinterest.However,themechanicalpropertiesoffluorinatedpolyurethanesusuallydeclinewithincreasingfluorinecontents.Theblendingoffluorinatedpolyurethaneswithnormalpolyurethanewascarriedouttoachievebalancedmechanicalandsurfaceproperties.Itwasfoundthatpolyurethanewithgoodmechanicalpropertiesandlowsurfaceenergycanbeobtainedbyaddingasmallamountoffluorinatedpolyurethane.Thefluorinatedsidechainscaneasilymigratetouppermostsurfacesoftheblendsuntillthefluorinelevelatthesurfacebecomesalmostsaturated.Ithasbeenshownfromcontactangle,XPSandAFMmeasurementsthatonlyaslittleas0.34wt%offluorinelevelisenoughtoproduceasurfacesaturatedwithfluorine,andthefluorinelevelattheuppermostsurfaceisonehundredtimeshigherthanthatintheblendbulk.Thefinaloutersurfacestructuresofthepolyurethaneblendwereindependentofthecontentofthefluorinatedpolyurethaneintheblendsduetothesurfacessaturatedbyfluorine.
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.
简介:Segmentedblockcopolymerbasedonnylon6(N6)andpolyethyleneoxide(PEO)withstochiometricratiowassynthesizedviaatwo-stepprocess.ThefirststeprepresentsendcappingofN6inthepresenceofadipicacidleadingtocarboxyterminatedN6,andthesecondoneispolycondensationofthelatterproductwithPEOinthepresenceofcatalystandthermostabilizertoformahighmolecularweightmulti-blockcopolymer.SeveralmethodswereappliedtocharacterizethesynthesizedcopolymersuchasFouriertransforminfraredspectroscopy,protonnuclearmagneticresonancespectroscopy,differentialthermalanalysis,differentialscanningcalorimetry,X-raydiffractionandatomicforcemicroscopy.Theobtainedresultsconfirmedthemulti-blockstructureforcopolymerwithaveryhighdegreeofmicro-phaseseparation.Atomicforcemicroscopymicrographsindicatedthatthemorphologywasthedispersionofhighstiffnessnanostructuredpolyamide(PA)domainsintheamorphousregionofPEOmatrix,whichcanbeveryimportantintheirperformanceformembraneprocesses.
简介:包含磷氮(MSMM-Al-P)的新奇包含的火焰retardant被与聚酰胺66包含准备(PA66-MSMM-Al-P)为聚酰胺6的火焰延迟(PA6)。结构和PA66-MSMM-Al-P的热性质被Fourier变换红外线的光谱学,X光检查光电子光谱学和thermogravimetric分析描绘。包含火焰retardants(MSMMAl-P和PA66-MSMM-Al-P)的PA6易燃被限制的氧索引测试,垂直燃烧测试和锥热量计调查。火焰retardancy和锥calorimetric分析在flame-retardantPA6建议了在PA66和MSMM-Al-P之间的synergistic效果。flame-retardantPA6的热稳定性也被调查。
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?
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.
简介:PolysaccharidecoatedPLAnanoparticlesbearingaldehydegroupswerepreparedbydialysisofDMSOsolutionofcholesterolhydrophobic-modifieddextranpolyaldehydeandPLAagainstwater.Theaveragediameterofthenanoparticleswasabout160nm,andthesizedistributionwasnearlyhomogenous.ThenanoparticleswerefunctionalizedsimultaneouslywithCD71andEGFRantibodythroughtheSchiff'sbasereaction,andthenradiolabeledwith~(99m)Tc.Afterperfusedtheradiolabelednanoparticlesintotumor-bearing...
简介:Insitucompatibilizationoflowdensitypolyehylene(LDPE)(30%)andnylon-6(70%)blendsthroughone-stepreactiveextrusionusingt-BuOOHasaninitiatorandlowmolec-ularweightinterfacialagentsascompatibilizerswasstudied.Thecompatibilizercontainedalongchainbydrocarbon,doublebondandtwopolarfunctionalgroupswhichwascapableofreactingwithbothLDPEandnylon-6inthepresenceofinitiatortoformacopolymerattheinterfaceofthetwopolymerphases.Theextrudedblendsexhibitedsignificanten-hancementintheircompatibilitybasedonmorphological,thermalanalysisandmechanicalstudies.Theeffectofthehydrocarbonchainlengthandstructureofthefunctionalgroupofthecompatibilizerwasalsoexamined.Itwasfoundthatblendspreparedbyusingthecompatibilizercontaininglongerhydrocarbonchainandamidegrouphadbettermechanicalproperties.
简介:LigandeffectofthecatalyticsystemWCl6-Et2AlClforringopeningmetathesispolymerization(ROMP)ofdicyclopentadiene(DCPD)wasinvestigated.Theexperimentalresultsshowthataddingstericallyhinderedphenol-2.6-di-tert-butylcresylol(DTBC)inthecatalyticsystemnotonlycanobviouslyincreasethemonomerconversionofpolymerizationbutalsoimprovethemechanicalproperties,suchasnotchedimpactstrength(NIS),tensilestrength(TS)ect.,ofthesynthesizedpolydicyclopentadiene(PDCPD),Asimilareffectcanbeobservedbyusingastericallyhinderdpolymericphenol-linearphenolformaldehyderesin(LPF)asaligand.
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.