简介:Theglassytransitionofthepolyethyleneterephthalate(PET)sampleswhichhavebeensubjectedtosolventinducedcrystallization(SINC)wasinvestigatedbymodulateddifferentialscanningcalorimetry(MDSC)anddensitymeasurement.Thedif-ferentialofheatcapacitysignal,dC_p/dTfromMDSC,wasusedtomonitortheSINCprocess.ItrevealsthattheT_gtemperatureshiftstohighervaluewiththeadvancementofSINC.Whenthetoluene-immersingtimewaslonger(168h),thedetectionofT_gbecomemoredifficult,becausesomesmallerpeaksemergedatthelowertemperaturesandtheseareexplainedasthemovementofsmallsegmentsintheamorphousregion.TheseobservedresultsareduetothemorphologyandstructureintroducedbytheSINCprocess.
简介:Theeffectsofinterfacialmodifieronthemechanicalpropertiesofkaolin-filledpolyamide6(PA6)havebeenstudied.Theinterracialinteractionbetweenpolyamide6andkaolinhasbeencharacterizedbymeansofinfraredspectroscopy(IR)andscanningelectronmicroscopy(SEM).TheresultsshowthattheroleoftheinterracialmodifierliesinforminganelasticinterlayerwithgoodadhesionbetweenkaolinandPA6.Acompositewithhighimpactstrength,hightensilestrengthandhighelasticmoduluscanbeobtainedbyinsertingtheelasticinterfacialmodifierintotherigid-particle-filledpolymersystem.
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: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: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.