Acyclic diene metathesis (ADMET) polymerization : the synthesis of well-defined model polymers for polyolefin materials

185 Pages·1997·3.9 MB·English

by  Valenti, Dominick J.

ACYCLICDIENEMETATHESIS(ADMET)POLYMERIZATION:
THESYNTHESISOFWELL-DEFINEDMODELPOLYMERSFOR
POLYOLEFINMATERIALS
By
DOMINICKJ.VALENH
ADISSERTATIONPRESENTEDTOTHEGRADUATESCHOOL
OFTHEUNIVERSITYOFFLORIDAINPARHALFULFILLMENT
OFTHEREQUIREMENTSFORTHEDEGREEOF
DOCTOROFPHILOSOPHY
UNIVERSITYOFFLORIDA
1997
Thisdissertationisdedicatedtomyfamily: Anthony,Patricia,andJulia
Volenti,allofwhomhaveprovidedmewithunlimitedsupport,confidence,
loveandstrengthtoachieveanygoalorchallengeintheknownuniverse.
ACKNOWLEDGMENTS
IwouldliketofirstacknowledgeDr.GuyMattsonforintroducingme
totheworldofpolymerchemistryandforhisfaithinmyabilitiesfromthe
beginning.
SpecialthanksareextendedtoDr.ChrisMarmoandDr.JasonPortmess
whoinstigatedmyinterestinADMETchemistry. Sincere thanksare
extendedtoallthemembersoftheWagenergroup,pastandpresent: Dr.K.
Brzezsinka,Dr.J.Anderson,Dr.J.O'Gara,Dr.D.Tao,Dr.H.Tamura,Dr.J.
Konzelman,J.Reichwein,F.Gomez,S.Cummings,T.Davidson,D.Tindall,
M.Watson,S.WolfeandL.Williams.
IwouldalsoliketorecognizethecooperationofDrs.R.Duran,J.
Reynolds,K.WagenerandG.Butlerthathascreatedaninstituteofvast
resources,knowledgeandfundingforthisandotherscientificpursuits.
Sincerethanksarealsoextendedtothepastandpresentmembersof
theDuranandReynoldsgroupsfortheircontributionsandsupportofmy
researchgoals. SpecificrecognitionisextendedtoJ.Batten,Dr.A.Kumar,D.
Cameron,Dr.P.Balanda,andDr.M.Divertiforsignificantcontributionsof
scientificknowledgeandphilosophicalideas.
GratefulacknowledgmentforfundingisgiventotheNationalScience
FoundationandTheDowChemicalCompany. Specialrecognitionis
extendedtoSteveHahnfromDowforhiscontributions,ideas,andfaithin
thisprojectfromstarttofinish.
RespectsgotoD.Panosian,T.Nguyen,J.Miller,L.Wolert,andN.
Moralesforboundlessfriendship,supportandthoughtfulness.
FinallyIwouldliketothankDr.Wagenerforbelievinginmyabilities
andprovidingnearlyunlimitedresources,freedomandknowledgethathave
madethisresearchandmygraduateeducationpossible.
TABLEOFCONTENTS
page
ACKNOWLEDGMENTS
iij
ABSTRACT viii
CHAPTERS
1 INTRODUCTION 1
HistoryofPolyethyleneandRelatedPolymers 3
DiscoveryandSynthesisof"Polymethylene" 3
SynthesisofPolyethyleneviaRadicalChemistry 6
Synthesisof"Polyethylene"(HeterogeneousZieglerCatalysts) 9
Synthesisof"Polyethylene"(HomogeneousZieglerCatalysts) 12
Copolymerizationofcc-olefins 15
Structure-PropertyRelationshipsofPolyolefins 18
Crystallinity,Morphology,andMeltingofFlexibleChain
Macromolecules 20
ThermalBehaviorandChainStructure 23
MetathesisPolymerization 27
RingOpeningMetathesisPolymerization(ROMP)
andWellDefinedAlkylidenes 27
AcyclicDieneMetathesisPolymerization(ADMET) 30
ADMET: StepCondensationMethodtoProducinga-Olefin
PrecursorPolymers 34
2 EXPERIMENTAL 36
InstrumentationandAnalysis 36
MaterialsandTechniques 38
SynthesisandCharacterization 39
SynthesisofSymmetricalAlkyl-SubstitutedTerminalDienes 39
AlternativeEnolateDisplacementReactionsforthe
SynthesisofCompoundsla,andlb 45
TAWeilrtttteiiragnrayMtieavtlehcooMhdeotlhsoydnsthefsoristhaendSyRnetdhuescitsioonfCompounds(5a)-(5c) ....555423
ADMETPolymerizationsofMonomers(5a)and(5b) 57
GeneralMetathesisConditions 57
HydrogenationofPolymers(P5a)and(P5b) 60
AlcoholMonomerSynthesis 61
ADMETPolymerizationsofAlcoholMonomers(Al),(A2),(A3) 64
GeneralMetathesisConditions 64
HydrogenationofPoly[l,10-Undecadiene-6-ol](HPA2) 66
PreliminaryAlcoholDimerizationExperiments 68
3 DESIGNANDSYNTHESISOFSYMMETRICALALKYL-
SUBSTITUTEDTERMINALDIENES 71
DesigningtheTargetMonomers 72
SynthesizingtheTargetMonomer 75
P-KetoEsterSubstitutionMethod 75
EnolateAlkylationofEthylAcetoacetateandthe
Retro-ClaisenCondensation 80
Reduction,Tosylation,andHydrideDisplacement 87
DealkoxycarbonylationoftheKetoEster 88
WittigMethod 91
MalonicEster,Di-GrignardandLactoneMethods 93
Organometallic/Tert-AlcoholMethod 95
Conclusions 100
4 ADMETMODELINGOFBRANCHINGINPOLYETHYLENE:
THESYNTHESISOFMACROMOLECULESWITH
PERFECTLYSPACEDMETHYLBRANCHES 101
ModAelDiMPnoEglTPyomlMeyoredtsehylynitlnheegnseiosfBviraanAcDhiMnEgTinPolyethylene 111000146
Hydrogenationoftheunsaturatedpolymer 113
ThermalAnalysisofMethylSubstitutedPolyethylene 120
ThermalAnalysisofADMETMethylSubstitutedPolyethylene 122
Conclusions 128
5 THEDIRECTSYNTHESISOFWELL-DEFINEDALCOHOL
FUNCTIONALIZEDPOLYMERSVIAACYCLICDIENE
METATHESIS(ADMET)POLYMERIZAHON 130
AlcoholFunctionalizedPolymersviaMetathesis 132
TMhoenvoiDamirAeerDctMDEeSysTnitghnesainsdoSfynAtlhceoshioslFunctionalizedPolymers 113356
ADGMeEneTraPlolAymDeMriEzTatPioolnyomferHiyzdartiooxnysFunctionalizedDienes 114400
Polymerizationof6-(4-Pentene)-l-Heptene-7-ol(Al) 141
Polymerizationof6-Methyl-l,10-Undecadiene-6-ol(A3) 145
Polymerizationofl,10-Undecadiene-6-ol(A2) 146
HydrogenationofPoly(6-Hydroxynonenylene)PA2 150
ThermalAnalysisoftheAlcoholContainingPolymers 152
PreliminaryDimerizationExperiments 156
Conclusions ....160
REFERENCES 161
BIOGRAPHICALSKETCH 173
AbstractofDissertationPresentedtotheGraduateSchool
oftheUniversityofFloridainPartialFulfillmentofthe
RequirementsfortheDegreeofDoctorofPhilosophy
ACYCLICDIENEMETATHESIS(ADMET)POLYMERIZATION:
THESYNTHESISOFWELL-DEFINEDMODELPOLYMERSFOR
POLYOLEFINMATERIALS
By
DominickJ.Valenti
August1997
Chairman: ProfessorKennethB.Wagener
MajorDepartment: Chemistry
Asyntheticmethodhasbeendesignedtofacilitatethesynthesisof
target monomers required for the preparation of perfectly branched
polyethylene modelpolymers. Thesepolymerscanbeused tobetter
understandtherelationshipsbetweenbranchinginpolyethyleneandits
ultimatebehavior. Symmetricalalkyl-substitutedalphaomegadieneswere
synthesizedusingasix-stepprocedureinvolvingtwoenolatedisplacement
reactions,aretro-Claisencondensation,anesterreductionfollowedbya
tosylation,andahydridedisplacementreaction. Purityoftheresulting
monomerswasgreaterthan99%.
ThealkylsubstitutedmonomerswerecondensedusingSchrock's
molybdenumalkylidene(CF3)2CH3CO]2(N-2,6-C6H3-i-Pr2)Mo=CHC(CH3)2Ph
forming well-defined alkyl-substituted polyethylene prepolymers.
Quantitativehydrogenation(byNMRanalysis)oftheresultingunsaturated
polymerswasachievedusingamodificationoftypicaldiimidereduction
procedures. Theresultingpolyethylenepolymers'containbranchpoints
occurringatevery9or15carbons,respectively. Thesesamplesareidealwith
regardtowell-definedchainbranchingandprecisebranchdistribution.
Presently,thishighorderofregularityinpolyethylenecopolymerscannotbe
obtained by any other method. Thermal analysis ofthesepolymers
demonstratestheuniquebehaviorofthesematerials. Thepresenceof
perfectlyspacedmethylbranchesresultsinasignificantdropinthepolymers'
meltingpointwithinaverynarrowrange.
Thesynthesisofwell-definedprimary,secondary,andtertiaryalcohol
functionalizedADMETpolymerswasalsoaccomplishedusingasimilar
methodology. Unsaturatedpolymersofthistypecanbehydrogenatedina
similarmannerproducinganewseriesofethylene-vinylalcoholcopolymers
exhibitingprecisechemicalregularity.
CHAPTER1
INTRODUCTION
Researchinpolymerchemistryduringthepastfivedecadeshas
resultedinthesignifigantadvancementofmacromoleculesasmaterialsin
technicalandnontechnicalapplications. Weallhavebecomeeveryday
consumersoftheproductofthisresearch,fromtheclothesweweartothe
materialsusedtoprintthisdocument. Advancementssuchasthesedonot
occurrapidly,butratherarederivedfrompatientworkleadingtothe
fundamentalunderstandingneededtocreatepolymersandtailortheir
physicalproperties.
The dissertation represents a contribution to this fundamental
research. Theworkpresentedhereindescribesthecreationofnewtechniques
thatofferuniquecontroloverapolymer'smicrostructure,whichinturncan
haveanimportanteffectonensuingphysicalproperties. Thiscontrolof
microstructureisdemonstratedbythesynthesisofmodelpolymerswithwell
definedstructuresthatcanbeusedtoelucidatetheeffectofmolecularchanges
onthebehaviorofthepolymer. Alsodemonstratedhereinistheabilityto
use Lewis basic/protic groups toward the synthesis of unsaturated,
functionalized polymers via acyclic diene metathesis (ADMET)
polymerization. Thesepolymersthencanbefurtherhydrogenated,resulting
inthedirectsynthesisofsaturatedpolyalcohols.