The reaction mechanisms of the epoxy resin with the amine hardener were analyzed by molecular simulation, and the system was found to shorten curing time at room temperature with high heat resistance. At first, the activation energies were calculated for the reaction between the epoxy and the amine, and confirmed by the experiment. It was confirmed the correlation between the calculation and the experiment. Next, it was expected the cross-link density would increase for the resin systems in which the activation energies of the self-polymerization reaction are lower than those of the addition reaction. It was confirmed the increased cross-link density and Tg for the systems by DMA. Finally, the room-temperature cure type adhesive with high heat resistance and rapid curability was developed based on the mechanism.

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Thesurfacetreatmentofglassbeadsbysilanecouplingagenthavingmercaptogroupwascarriedout.Thetreatedglassbeadswereincorporatedwithpolyisoprene,andthenvulcanized.Theeffectsofamountofchemisorbedsilaneandalkoxygroupnumberofsilaneonthemechanicalpropertiesofthefilledcompositewereinvestigated.Forthispurpose,silaneswithdialkoxyandtrialkoxystructureswereused・Theamountofchemisorbedsilaneontheglassbeadsurfacewasvariedfromtwotoninetimesoftheamountrequiredformonolayercoverage.Thestressatthesamestrainincreasedbythesilane-treatmentofglassbeads,anditwashigherinthedialkoxystructurethanthetrialkoxystructure.Therewasnosignificantinfluenceofamountofchemisorbedsilaneonthestressfortrialkoxysilanestructure.Whereas,thestresswasinfluencedbytheamountofchemisorbedsilaneandthemaximumstresswasobservedatfivetimesofthesilaneamountrequiredformonolayercoverageforthedialkoxystructure.Thetendencyofthestressvalueshowedagoodrelationwiththeamountofunextractedpolyisoprenemeasuredbyanextractiontestofsilane-treatedglassbeads/polyisoprenemixtureinatetrahydrofuransolution.Thereinforcementeffectbythesilanetreatmentofglassbeadswasfoundtobeaffectedstronglybytheentanglementofsilanechainandpolyisoprenerubbermoleculesintheinterfacialregion.

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Segmented polyurethanes (SPUs) were synthesized using 4,4'-diphenylmethane diisocyanate (MDI), poly(oxytetramethylene) glycol (PTMG-2000) and different weight ratios (100/0, 90/10, 75/25 and 50/50) of 1,4-butanediol (BD) and 1,1,1-trimethylolpropane (TMP) as the curing agents. Chemical crosslinks were incorporated into SPUs to control their microaggregation structure. Swelling behavior was evaluated to determine the crosslink density and the molecular weight between crosslinkingpoints (Mc). It was revealed that while crosslink density increased, Mc decreased with an increasing TMP content. Polarized optical microscopy (POM) and differential scanning calorimetry (DSC) revealed that the degree of microphase separation of the SPU became weaker as TMP was increased. The surface free energy of the SPUs was determined by measuring the contact angle. The effect of the curing agent ratios in SPU on its adhesion properties was investigated using the T-peel test. The T-peel strength increased in inverse proportion to crosslink density because hard segment chains, which can be melted by heating, strengthen the interaction between SPUs and the aluminum substrate.The T-peel fracture behavior of SPUs after peeling from the substrate was examined by optical microscopy. Three failure modes were observed in these SPUs, namely interfacial failure, cohesiveinterfacial failure and cohesive failure.

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