Epoxyresinterminatedpolyurethanes(ETPU)werepreparedwithpolyurethaneprepolymerswhichwerereactedwithfourkindsofmacroglycols(Mn=2000,Polyoxypropyleneglycol:PPG,polyoxytetramethyieneglycol:PTMG,polycarbonateglycol:PCG.1.2-polybutadieneglycol:1.2-PEG),diisocyanate(MDI)andbisphenol-Atypeepoxyresinwithonesecondaryhydroxygroup.10to50phrofETPUwereaddedtotypicalbisphenol-Atypeepoxyresinandcuredbyadipicaciddihydrazide(ADH).TherelationshipbetweenpropertiesofcuredepoxyresinsandchemicalstructuresofthepolyurethanechainofETPUwasinvestigated.AllETPUshowedtheimprovementeffectofcuredepoxyresin.RegardingadhesionpropertiesPCG(C2N)systemhadconspicuouseffect,1.2-PBG(B2N)systemhadsmalleffect.ItwasfoundthatC2NsystemshowedthehighestfracturetoughnessinallETPU,PTMG(T2N)system,B2NsystemandPPG(P2N)system.inthatorder.Theresultsofscanningelectronmicroscopy(SEM)showedclearvisiblemicrophaseseparationinallETPU・Ontheonehand,thecaseofdynamicviscoolasticitysuggestedtwokindsofphases;theexistenceofcompatibleepoxyresin/ETPUanddispersedETPUparticlesinepoxyresinmatrixassea-islandstructure.

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