资源描述:
《新型石墨烯超高分子量聚乙烯纳米复合汇报材料》由会员上传分享,免费在线阅读,更多相关内容在行业资料-天天文库。
1、......pubs.acs.org/MacromoleculesNovelGrapheneUHMWPENanocompositesPreparedbyPolymerizationFillingUsingSingle-SiteCatalystsSupportedonFunctionalizedGrapheneNanosheetDispersionsMarkusStürzel,*,†FabianKempe,†YiThomann,†StefanMark,‡MarkusEnders,‡andRolfMülhaupt*,†FreiburgMaterialsR
2、esearchCenter(FMF)andInstituteforMacromolecularChemistry,UniversityofFreiburg,Stefan-Meier-Str.31,D-79098Freiburg,GermanyAnorganisch-ChemischesInstitut,UniversityofHeidelberg,ImNeuenheimerFeld270,D-69120Heidelberg,GermanyABSTRACT:Novelfamiliesofultrahigh-molecular-weightpolyethy-
3、lene(UHMWPE)nanocomposites,containinguniformlydispersed,functionalizedgraphene(FG)nanosheets,werepreparedbymeansofthepolymerizationfillingtechnique(PFT).Unparalleledbyanyothercarbonandboehmitenanocomposites,FG/UHMWPEexhibitedanunusualsimultaneousimprovementinstffness,elongationatb
4、reak,andeffectivenucleationofpolyethylenecrystallizationatonly1wt%FGcontent.FGnanosheetsareultrathinwithathicknessofonlyonecarbonatomandlateraldimensionsofseveralmicrometers.OwingtothepresenceofsurfacehydroxylgroupsontheFG,singleFG/methylaluminoxane(MAO)nanosheetscanbeeffectively
5、dispersedinn-heptane,thusenablingimmobilizationofanMAO-activatedchromium(Cr1)single-sitecatalystonFG.Incontrasttonanometer-scalecarbonblack(CB),multiwallcarbonnanotubes(CNT),graphite,andnanoboehmite,whichfailedtoformstabledispersions,FG/MAO/Cr1affordedthehighestcatalystactivities
6、andexcellentmorphologicalcontrol.Inpolymerizationfilling,theintegrationofananoparticledispersionintothepolymerizationprocesseliminatedtheneedforspecialsafetyandhandlingprecautionstypicallyrequiredbyconventionalcompoundingofnanoparticleswithultralowbulkdensities.学习好帮手......INTRODUC
7、TIONUltrahigh-molecular-weightpolyethylene(UHMWPE),withmolarweightsexceeding1million,iswell-knownforitsultrahightoughnesscombinedwithhighabrasionresistance,verylowfrictioncoeffcient,lowmoistureuptake,andexcellentchemicalstability.1Sheets,parts,andfibersareproducedfromUHMWPE.Applic
8、ationsrangefromwear-resistanttransportbe