学科分类
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12 个结果
  • 简介:Fourpolymer-supportedFe-Cotetrametallicclustershavebeenpreparedbyionexchangeandligandexchange.TheirstructureswerecharacterizedbyIR,UV/visiblediffusereflectancespectraandelementalanalysis,andbyanalogywiththereferenceclusterPhCH2NMe3FeCo3(CO)2.Thefourheterogenousclusterswereefficientcatalystsinthehydroformylationof1-hexene,turnovernumbersamountedto823—924withtheyieldof83.2—92.4%heptylaldehydesandratiosofnormalaldehydetoiso-aldehydeof1.2—1.6,theyarefacilitatedformingthenormalaldehydeincomparisonwiththehomogeneousanalogue.Forthepolymer-supportedclusterspreparedbyionexchange,thepolymer-cationpartshadnoobviouseffectontheactivityoftheclusteranion.Thepolymer-phosphinesubstitutedclusterpreparedbyligandexchangewasmorestablethantheclusterspreparedbyionexchange.

  • 标签: POLYMER-SUPPORTED Fe-Co tetrametallic cluster catalyst HYDROFORMYLATION
  • 简介:Thisworkdealswiththekineticsofco-condensationpolymerizationofAB2andABmonomers,givingexpressionsofthetwo-dimensionalmolecularweightdistributionfunctionandthenumber/weightaveragemolecularweightsoftheresultingcopolymers.Thetwo-dimensionalmolecularweightdistributiondependsontwoindices,nandl,whicharetherespectivenumbersofAB2andABunitsinacopolymerspecies.Theevolutionofthetwo-dimensionalweightandzdistributionsduringtheco-condensationpolymerizationhasbeenevaluatedsystematically.Finally,thetwo-dimensionaldistributionwastransformedintoaone-dimensionalmolecularweightdistributionwithonlyonevariable(themolecularweightoftheproductsinsteadofthedegreeofpolymerization).Thecalculatedresultsshowthatthehighlybranchedcopolymerhasaverybroadmolecularweightdistributionwhentheco-condensationpolymerizationapproachescompletion.

  • 标签: 共聚物 动力学分析 分子量分布 浓缩 AB2树脂 AB树脂
  • 简介:Poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/Organophilicmontmorillonite(PHBV/OMMT)nanocompositeswerepreparedandthebiodegradabilityofthePHBV/OMMTnanocompositeswasstudiedbyacultivationdegradingmethodinsoilsuspension.TherelationshipbetweenstructureandbiodegradabilityofPHBV/OMMTnanocompositeswasinvestigated.TheresultsshowedthatthebiodegradabilityofPHBV/OMMTnanocompositesdecreasedwithincreasingamountofOMMTanditwasrelatedtothenumberofPHBVdegradingmicroorganismsindegradationenvironment,theanti-microbialpropertyofOMMTandthedegreeofcrystallinityofthenanocomposites.

  • 标签: 生物降解能力 聚(3-羟基丁酸酯-co-3-羟基戊酸酯) 蒙脱土 纳米复合物 环境友好物质 可降解塑料
  • 简介:Synthesisofsuperabsorbentofstarch-graft-poly(patassiumacrylate-co-acrylamide)hasbeenstudiedbyinversesuspensionpolymerization.Inthispaper,theeffectsofreactionconditions,suchas,monomericconcentration,theamountofcross-linkingagent,ratioofwatertooil,reactiontemperatureandthebestconditionbeingabletoobtainthesphericalresinwereinvestigated.Experimentsshowthatthewater-absorbingresinisstrongandcapableofresistingpressureofretainwater.Itkeepstheshapeofparticlesafterabsorbingwater.Aftermixingwithsoil,itdoesnotbecomesticky,andthecoosstructurecanbetterretainair.Itjustfitagricultureandforest.Inaddition,thermogravimetricanalysisrevealedthesuperiorthermalstabilityofthegraftedproduct,anditslargesizeparticlesalsoreducesriskofairpollution.

  • 标签: 合成 超吸收剂 淀粉接枝聚(丙烯酸钾-丙烯酰胺) 逆向悬浮共聚合
  • 简介:Fromaneconomicalpointofviewboththequalityoftheionexchangeresinsandthetechnologyusedinthefieldofindustrialwatertreatmentareimportantforasuccessfulperformance.Ingeneral,twodifferenttechnologieshavebeenestablishedonthemarket:ThemaindiffernecesbetweentheCO-andcountercurrenttechnologeswillbediscussedanddataconcerningtherequirementofchemicalsforregenerationandthequalityofthedeionizedwaterwillbeopposed.Inadditionseveraldifferentvarietiesofthemoderncountercurrenttechnologies,developedandpatentedbyBayerAG,willbedescribedandtheadvantages,dependingontheapplicationandthedemandonthequalityofthedeionizedwater,pointedout.Inviewofstrongerregulationsconcerningtheconsumptionofregenerationchemicals,andwastewater,andalsobecauseofthesuperiorqualityoftheproducedwater,themarketshareofcountercurrenttechnologieswillcontinuetoincreaseworld-wide.

  • 标签: 拜耳反向电流系统 离子交换理论 拜耳逆流系统 相互流系统 水处理
  • 简介:Metalion-imprintedlycrosslinkedchitosanresin1andresin2werepreparedbytheuseofCu^2+andNi^2+astemplateionsandglutaraldehydeascrosslinkingagent,respectively,ThroughinvestigationontheadsorptioncapactiesandbindingconstantsforCu^2+,Ni^2+andCo^2+ionsonchitosanresins,resin1andresin2exhibittheadsorptionselectivityforthemixturesolutionof1L1Cu^2+andNi^2+ions.Theadsorptionselectivityofmetalion-imprintedresinsfortheirtemplateionsinmuchhigherthanthatofuncrosslinkedchitosanresin.

  • 标签: 金属离子分离 脱乙酰壳多糖合成树脂 吸附选择性
  • 简介:Blendsofpoly(3-hydroxybutyrate-co-3-hydroxyhexanoate)(PHBHHx)andpoly(butylenesuccinate-adipate)(PBSA),bothbiodegradablesemicrystallinepolyesters,werepreparedwiththeratioofPHBHHx/PBSArangingfrom80/20to20/80bymeltmixingmethod.Differentialscanningcalorimetry(DSC),thermogravimetryanalysis(TGA),dynamicmechanicalthermalanalysis(DMA),polarizingopticalmicroscopy(POM)andwideangleX-raydiffractometer(WAXD)wereusedtostudythemiscibilityandcrystallizationbehaviorofPHBHHx/PBSAblends.ExperimentalresultsindicatethatPHBHHxisimmisciblewithPBSAasshownbythealmostunchangedglasstransitiontemperatureandthebiphasicmelt.

  • 标签: 热性质 结晶行为 聚(3-羟基丁酸基-共-3-羟基己酯)聚(丁烯琥珀酸酯-己二酸) 可混和性