简介：ThePVCservesofmacroporoussulfoniccation-exchangeresinswerepreparedbythesulfonationofamacroporousPVCbeadwithconcentratedsulfonicacidorchlorosulfonicacid.theresultingsulfonicresinwasemployedintheinvestigationofcatalyticesterificationandsolfteningofwater,Theresultsshowthattheyieldsofestersreach60.0-84.4%accordingasdifferentfattyacidsandalcohols,therefractiveindexesofestersobtainedresemblethosereportedinthereferencesbasically,meanwhile,345Lsoftenedwaterwhichholds≤0.06mmol/Lhardnesswouldbepreparedby1Lwetsulfonicresinreusingfor4times.Theresultingsulfonicresinswouldhave1.6-2.0or2.5-3.0mmol/gexchangecapacitybyusingconcentratedsulfonicacidorchlorosulfonicacidassulfonatingagent,respectively,Thesulfonicresinhasamacroporousstructuretakingthemorphologywithagglomeratesofminutelysphericalgelparticlesascharacteristic.

简介：Aseriesof'hairy-rod'polyimides,BBPA(n),withmultiplealkylsidechainswaspreparedfrom3,3′,4,4′biphenyltetracarboxylicdianhydride(BPDA)and4,4′-biphenyldiaminesubstitutedinthe2,2′-positionswithbenzoate,whichwassubstitutedinthe3,4,5-positionswithethersidechainsofvaryinglengths.Thenumberofthemethyleneunits,n,inthesealkylsidechainswereinevennumbersrangingfrom8to18.Combiningtechniquesofone-dimensional(1D)and2Dwideanglex-raydiffraction,1DsmallangleX-rayscattering,differentialscanningcalorimetryexperiments,itwasfoundthatthisseriesof'hairy-rod'polyimidespossessamicro-phaseseparationbetweenthebackbonesandsidechains.Thisledtotheformationoforderedstructuresintwodifferentlengthscales,ofwhichbotharehexagonalpacking:oneisattributedtothealkylsidechainsonthesub-nanometerscale,andanotherisforthewholepolymerchainsonthenanometerscale.Thedevelopmentofthehexagonalstructureonthesub-nanometerscalewascriticallydependentuponthelengthsofthealkylsidechains.Threerelaxationprocesseswerecapturedbydynamicmechanicalanalysis,i.e.,segmentalmotionofthebackbones,α,themeltingofthesidechaincrystals,β1,whichexitsonlyforthematerialswithlongersidechains(n=18,16);andthesubglassrelaxationofsidechains,β2.Thepeakrelaxationtemperatureoftheαprocessdecreasedwithincreasingthelengthofsidechains,whiletheoneoftheβ2processincreased.Theactivationenergyoftheαrelaxationwasrelativelyindependentonthelengthofsidechain,whereas,β2processshowedtheincreasingofactivationenergywithincreasingthelengthofsidechains.