学科分类
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29 个结果
  • 简介:两个都与高chemoselectivity介绍芳香、脂肪族的主要的氨基的组的一个一步舞过程被开发。三位字节州的丙酮从聚合电影底层的C-H契约和是积木和氨基的组搬运人的酚的O-H契约提炼氢原子。作为结果,二种自由激进分子,聚合物底层的限制的以碳为中心的链激进分子和活动以氧为中心的含苯氧基的激进分子,被产生。然后,公司契约被在这些二种自由激进分子之间的联合反应形成。p-Tyramine和p-aminophenol被用作氨基的搬运人。氨基的组的成功的介绍被水合同角度(CA)的大小表明到LDPE,BOPP和宠物电影底层上,紫外系列(紫外),X光检查光电子光谱学(XPS)并且荧光灯显微镜学。处理因素p-tyramine和p-aminophenol的集中,和丙酮/水的比率例如紫外光的紧张和照耀时间,被调查。优化进程参数如下:紫外轻紧张9500W/cm2;为BOPP和LDPE的照耀时间18min,为宠物的22min;丙酮/水=的比率1;并且p-tyramine和p-aminophenol的集中15%为BOPP和LDPE,1%为宠物。基于紫外吸收度,聚合底层上的氨基的组被估计在6.3浥汵楳湯瀠汯浹牥穩瑡潩獮眠瑩?慣楴湯捩?湡潩楮?档牡敧?湩的范围吗?

  • 标签: 氨基酸组成 聚合物薄膜 苯酚衍生物 光诱导 苯氧自由基 X射线光电子能谱
  • 简介:TiCl_4/MgCl_2/claycompoundcatalystwaspreparedbychemicalreaction.Exfoliatedpolypropylene(PP)/claynanocompositesweresynthesizedbyinsitupolymerizationwiththiscompoundcatalyst.Effectsofpolymerizationtemperature,polymerizationtime,propylenepressure,solventconsumptionandpre-treattimeofcatalystoncatalystactivityandcatalyticstereospecificitywerestudied.Underoptimalconditions,activityofthenano-compoundcatalystisabout88.3kg/(molTi·h).IsotacticityofPPobtainedinthenanocompositesisintherangeof89%-99%,anditsmeltingtemperatureisabout159℃.Theweight-averagemolecularweightofPPcanreach6.7×10~5-7.8×10~5,andthemolecularweightdistributionisbetween7.7and7.9.

  • 标签: 纳米复合催化剂 纳米复合材料 催化剂制备 原位聚合 聚丙烯 粘土
  • 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.

  • 标签: 结晶化 聚烯烃 聚甲基丙烯酸甲脂 液晶相
  • 简介:Kineticsofchloride/sulfate,chloride/nitrateandnitrate/sulfateforwardexchangesandreverseexchangesatsolutionconcentrationsof1N,0.2Nand0.02Non201×7strongbaseanionexchangeresin,respectively,havebeenexaminedat25℃.Itisfoundthattheforwardandthereverseexchangeratesofthetwogivenionsatlowsolutionconcentration,respectively,underidenticalconditionscanbecontrolledbydifferentmechanisms,whilethoseathighsolutionconcentrationareallcontrolledbyparticlediffusion.Theternaryexchangeratesofsulfate/(chloride+nitrate)andnitrate/(chloride+sulfate)havealsobeenexamined.

  • 标签: 二元离子交换 硫酸根-氯离子-硝酸根离子-201×7体系 三元离子交换 动力学
  • 简介:Dithia-monoaza18-Crown-6anditsimmobilizationproduct,silica-bound1,7-dithia-4-aza-10,13,16-trioxa-cyclooctadecaneviaaspacerofthreecarbonatoms,anditsplatinumcomplexhavebeensynthesized.Itisfoundthattheplatinumcomplexisanefficienthydrosilylationcatalystforolefins.TheXPSdataoftheplatinumcomplexarereported.

  • 标签: 二氧化硅 铂络合物 铂配合物 1 7-硫-4-氮杂-10 13 16-氧硫杂环十八烷
  • 简介:Inthispaperstudyonthepropertyandmechanismofadsorptingrheniumfromaqueoushydrochloricacidbyusingmethylphosphorousaciddimythylheptylesterlevextrelresin(CL-P350)isreported.Theeffectsoftime,acidity,concentrationofrhenium,andtemperatureontheadsorptionofrheniumwereinvestigated.ThemechanismofadsorptingrheniumwasdiscussedbychemicalanalyticandIRmethod,anddynamicadscrptionandelutionwerestudied.Experimentalresultsshowthattheadsorptionequilibrationisreachedin4min,thedistributioncoefficient(D)ofRe(Ⅶ)increaseswithincreaseofconcentrationofHClandreachesmaximum3.0-4.0moL/LHCl.ReO4^-istakenupbyionassociationmechanismandcanbedescribedbyLangmuirequationoftheequilibriumstate.ThethermodynamicparametersintheadsorptionprocessofReO4^-havebeendeterminedtobe:ΔH=-29KJ/moL,ΔG=-25KJ/moLandΔS=-13.5J/moLrespectively.Thesaturationadsorptioncapacityofrheniumis19.2mg/gwhenthesolutioncontaining0.372g/LReand3.0mol/LHClwaspassedthroughtheresincolumn.Therecoverypercentageofrheniumis98.4%whiledistilledwaterwasusedasaneluent.

  • 标签: 吸附性铼 中性磷 盐酸 高铼酸钾
  • 简介:Opticallyactive(R)-(+)-2,2’-bis(2-trifluoro-4-aminophenoxy)-1,1’-binaphthylwaspreparedfrom1,1’-bi-2-naphthol.Theopticallyactivearomaticpolyimidewasalsosuccessfullysynthesized.Thisnewpolymerhasgoodsolubility,thermalstabilityetc.Itsspecificrotationwasfoundtobe+174°,anditschiropticalpropertywasalsostudied.

  • 标签: Optical ACTIVITY 1 1′-Bi-2-naphthol POLYIMIDE