超支化聚乙烯的制备与功能化

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1、浙江大学硕士学位论文AbstractHyperbranchedpolyethylene(HBPE)isanewtypeofpolyethylenematerialsinadditiontolow-densitypolyethylene(LDPE)，high—densitypolyethylene(HDPE)，andlinearlow·densitypolyethylene(LLDPE)．Ithasadentrimer-likecompactglobularstructure，andshowsNewtonianflowbehaviord

2、uetotheabsenceofchainentanglements．HBPEexhibitsbettersolubilityandlowersolutionviscositycomparedtolinearpolyethylene，whichhasattractedgreatattentioninresearchanddevelopment．Forexample，branchinginpolyethylenepreparedwithnickel(II)·orpalladium(II)-basedlatetransitionmetal

3、catalystsCanvaryfromhyperbranchedtomoderatelybranchedtolinear．Theirmaterialspropertiesrangefromsoftwax，toelastomer,torigidplastic，respectively．Thisspecialcharacteristichelpstoimproveprocessingofpolyethyleneandbroadensitsrangeofapplications．However,HBPEhasnotyetachievedi

4、ndustrialization，itsrelationshipsbetweenchainstructLlreandmaterialspropertiesareyettobeestablishedanditsapplicationsneedtobefurtherexplored．ChemicalmodificationandfunctionalizationCanintroducenovelstructuresandtailor-madepropertiestothistypeofmaterialsandthusexpandtheir

5、applicationhorizon．Inthisthesis，theprogressandprospectinthepreparation，structure，andproperties，aswellasapplicationsofHBPEmaterialswerereviewed．HBPEsampleshavinghighmolecularweightandhighbranchingdensityweresynthesized、析tIlappropriatediiminenickel(II)-basedlatetransition

6、metalcatalysts．Thestructureandpropertiesofthesesampleswerestudiedusing13CNMR，1HNMRandDSC．HBPEwasfunctionalizedthroughgraftingmaleicanhydride(MAH)andotherchemicalmodifications．Foracomparisonpurpose，variouspolyolefinsweregraftedwithMAH．Theirgraftingdegrees(GD)，gelcontents

7、，lossinchaindegradation，molecularweightofthemodifiedpolymerswerestudiedinparallel．N，N—diethylcinnamamide(DECA)，havingaringconjugatedwithadoublebondandnitrogen,WassynthesizedandusedIV浙江大学硕士学位论文asaninhibitortosuppressthesidereactions．Twokindsoflatetransitionmetalcatalysts

8、weresynthesized：bi(2,6一diisopropylphenyl)butanediiminenickeldibromide(IBNB)andbi(phenyl)amyldiiminenickeldibro