简介:Threepolymericadsorbentswithhydrogenbondingacceptors,methylamine,N-methyl-acetamideandaminotri(hydroxymethyl)methanemodifiedresinsaresynthesizedfromchloromethylatedX-5resin.AdsorptionisothermsofphenolandtheophyllineontothethreemodifiedresinsandtheoriginalX-5resinfromaqueoussolutionaremeasured.TheresultsshowthatadsorptionofcompoundswithhydrogenbondingdonorontomethylamineandN-methylacetamidemodifiedresinsisenhancedascomparedwiththatontoX-5resin,andadsorptionmechanismbetweentheadsorbentsandtheadsorbatesismainlybasedonhydrogenbondingandhydrophobicinteraction.Whileadsorptionofcompoundswithhydrogenbondingdonorontoaminotri(hydroxymethyl)methanemodifiedresinisloweredascomparedwiththatontoX-5resin,andadsorptionmechanismbetweentheadsorbentandtheadsorbatesismainlybasedonhydrophobicinteraction.
简介:Thetransitionsandmorphologyofaseriesofmain-chainliquidcrystallinepolymerwithX-shapedmesogenswerestudiedbymeansofDSC,SALSandpolarizingmicroscopytechniques.Aneven-oddeffectwasobservedforsampleswithdifferentsizeofthesubstituentsonthemesogenends.Theisotropizationprocesswassimilartothatofmain-chainpolymerswithrod-likemesogens.Nocrystallizationwasdetectedforspecimenscoolingdownfromtheirisotropicmeltstate.Howevertwoofthesamplesmaycrystallizeincoolingprocessdirectlyfromtheliquidcrystallinestate.
简介:Thepolymerizationof1-octeneinitiatedbymethylalumoxane(MAO)-activatedNi(Ⅱ)-based-α-diiminecomplexes[(2,6-i-Pr)_2C_6H_3-DAB(An)]NiBr_2wasinvestigated.Usingthiscatalyst,poly(1-octene)swithmolecularweightbetween100×10~3and400×10~3andpolydispersity(M_w/M_n)between1.3and1.5weresynthesizedsuccessfullybyvaryingreactiontimeatroomtemperature.Thepoly(1-octene)swereamorphouspolymersandcouldbewellsolubleintetrahydrofuran(THF).Afterfractionalprecipitation,poly(1-octene)swithnarrowmolecularweightdistributions(M_w/M_n≤1.12)wereobtained.Theirweight-averagemolecularweightsweremeasuredbygelpermeationchromatography(GPC)inconjunctionwithonlinemodelBI-MwAmultianglelaserlightscattering(MALLS),andtheirintrinsicviscositiesweremeasuredbyMaron'ssingle-pointmethod.ThekandavaluesinMark-Houwinkequation[η]=KM~αinTHFat40℃were0.089mL/gand0.61respectively.
简介:Thecopolymersofchloroethylmethacrylate(CMA),glycidylmethacry-late(GMA),andmethylmethacrylate(MMA)weresynthesizedinbenzenesolution.Theirbreadthsofthemolecularweightdistributionsare2.1and2.3,respectivelyThether-malstabilityofP(GMA-CMA)issuperiortothatofP(CMA-MMA).TheresolutionsofP(CMA-MMA)andP(GMA-CMA)photoresistswerefoundtobe0.1~0.16μmand0.17~0.2μm,respectively.
简介:Theinsertionof1,1-bis(1′-naphthyl)ethylenemonomerunitintotheactivepolystyrenechainendgreatlydecreasedthereactivityoftheactivechainendtothecarbonylgroup,andallowedthepolymericchainendtoreactonlywiththedoublebondinN-methacryloylcaprolactam,resultinginN-acylcaprolactamfunctionalizedpolystyrenein100%conversion.Newdiblockcopolymerofpolystyrenewithpolycaprolactamwassynthesizedbydirectreactionofthefunctionalizedpolymerwithcaprolactamwithoutaddingadditionalalkalimetalortheircaprolactamsalts.
简介:1-Ethoxycarbonylalkyldiphenylpolystyrylphosphoniumtriflatescanbeeasilypreparedbyquaternizingdiphenylpolystyrylphosphinewithethyl2-trifloxyalkanoates;basetreatmentofthesepolymer-supportedphosphoniumtriflatesaffords1-ethoxycarbonylalkylidenephosphoraneswhicharestableandundergosatisfactoryWittigreactions.
简介:The1,1'-binaphtholbasedoligomers3and7with3,3'-acetylene-phenylene-acetylenespacerwerepreparedfromBINOL1.ThehighopticalrotationvalueandCDspectrademonstratedthemainchainchiralityoftheoligomermolecule.TheUV-VISandfluorescentspectraevidencethecharacteristicsofconjugatedstructure.Incomparisonwitholigomer2bearing3,3'-acetylenespacer,theoligomers3and7havelongerefficientconjugationsegment,andtheirfluorescentquantumyields(φ)increased(0.60-0.65versus0.14).Extendingtheeffectiveconjugationsegmentwouldimprovethephotophysicalpropertiesofchiralconjugatedpolymers.``
简介:Newmodelcompound1H,1′H-Bis(benz-Δ^4-imidazoline)2,2′-spiro-titaniumdichloridewaspreparedandthestructureofthecompoundwasdeterminedby1R,MSandelementaryanalysis.
简介:BymeansoftheintensitytheoryofX-rayscatteringandthetwo-phaseconceptofhighpolymer,thebasicformulaofthecrystaUinityinblockcopolymershasbeenproposedafterthecorrectionsofatomic,temperature,absorption,Lorentzandpolarizationfactor.Applicationofthismethodtodifferenttypepoly(oxyethylene-styrene)blockcopolymersandthesametypeblockcopolymerswithdifferentEOcontentsindicatesthatthecrystallinityinpoly(oxyethylene-styrene)blockcopolymersincreaseswiththeincreaseoftheEOcontentanddecreasesintheorder:PEO-PS-PEO>PEO-PS>PS-PEO-PS.
简介:Anovelpolymercontainingthesucrosegroupwassynthesizedbyradicalpolymerizationfromanenzymaticallypreparedmonomer,1′-O-vinyladipoyl-sucrose(VAS).TransesterificationreactionofsucrosewithdivinyladipateinanhydrouspyridinecatalyzedbyanalkalineproteasefromBacillussubtilisat60℃for7daysgaveVAS(yield55%)withoutanyblocking/deblockingsteps.ThevinylsucroseestercouldbepolymerizedwithpotassiumpersulfateandH2O2asinitiatortogivepoly(1′-O-vinyladipoyl-sucrose)withMn=33,000andMw=53,200,Mw/Mn=1.61.Thepolymerwasbiodegradable.After6daysinaqueousbuffer(pH7),thisalkalineproteasecoulddegradepoly(1′-O-vinyladipoyl-sucrose)toMnofca.1080,Mw/Mn=3.30(37℃),andMnofca.5200,Mw/Mn=2.44(4℃).Thepolymercontainingthesucrosebranchwouldbeafunctionalmaterialinvariousapplicationfields.
简介:Thecopolymerizationofl-octenewithstyrenecatalyzedbyrareearthcoordinationcatalystshasbeenstudiedforthefirsttime.Somefeaturesandkineticbehavioraredescribed.Theoverallactivationenergyofthecopolymerizationwas22.2KJ/molandthecopolymerizationratecouldbeexpressedasRp=Kp[Nd][M]2.(=1.68×10-3L2/mol2.S,50℃,[Oct]/[St]=1).ThecatalyticactivityofvariousrareearthelementsinLn(naph)3forthecopolymerizationwascomparedandshowsthefollowingsequence:Dy,Y,Yb>Ho>Sm,Gd,Nd>Pr>Ce>La>Tm.Bothmonomersofl-octeneandstyreneinthecopolymerizationbyNd(naph)3-AlEt3havethetendencyofconstantproportioncopolymerization.Thestructureofthecopolymerswasstudiedby1H-NMR.
简介:ThephysicalandchemicalpropertiesofFFA-1ionexchangefiberhavebeencharacterizedwithIRspectrum,thermalanalysisandSEMmeans.ThepHtitrationcurve,swellingrate,mechanicalproperties,resistancedropoffilterlayeraswellasthedynamicadsorptionforSO2wasdetermined.TheseexperimentsprovidedtheessentialparametersforthepracticalapplicationofFFA-1materialinadsorptionoftoxicgases.
简介:Aseriesof1-naphthylmethylmethacrylate(NMMA)-methylmethacrylate(MMA)copolymersweresynthesizedonfreeradicalmechanism.ThereactivityratiosofNMMA(r1)andMMA(r2)werereportedtobe0.83and0.89,respectively.ThecharacterizationofthecopolymersbyusingIR,NMR,GPC,UVandfiuorescencespectrometrywasdescribedinthispaper.
简介:Opticallyactive(R)-(+)-2,2’-bis(2-trifluoro-4-aminophenoxy)-1,1’-binaphthylwaspreparedfrom1,1’-bi-2-naphthol.Theopticallyactivearomaticpolyimidewasalsosuccessfullysynthesized.Thisnewpolymerhasgoodsolubility,thermalstabilityetc.Itsspecificrotationwasfoundtobe+174°,anditschiropticalpropertywasalsostudied.
简介:Animprovedmethodisdevelopedbyusingstronglyacidiccationexchangeresin(001×1,H^+form)asacatalystforthesynthesisofdiphenyl1-(N-benzyloxycarbonyl-amino)alkanephosphonatesand1-(N-benzyloxycarbonylamino)alkanephenylphosphinicacidsinhighyields.