A Study On Mechanism Of The Co-Reaction Of Epoxy And Cyanate And The Mechanical Properties Of Epoxy/Glass Cloth/Hollow Glass-Bead Blend

In this paper, the mechanical properties and the thermal properties ofepoxy are modified with the cyanate resin and glass cloth/hollowglass-bead, and the mechanism of co-reaction of epoxy and cyanate isinvestigated. Epoxy was modified with the cyanate resin ,four systems werestudied—— non-catalyzed,Cu(AcAc)2-catalyzed, manganese octoate-catalyzed and copper octoate- catalyzed. The temperature of the reaction are researched by differentialscanning calorimeter (DSC), the transformations of chemical speciesduring the isothermal and heating up process were explored by Fouriertransform infrared spectroscopy (FTIR); the changes of the carbonic-framework of polymer were analyzed by Nuclear magnetic resonance(NMR). Some conclusions can be drawn as follows: the reaction occursin two steps: cyclotrimerization of cyanate to produce triazine rings, aswell as the formation of some intermediate products, and co-reaction ofepoxy and triazine rings to form oxazlidinone rings in the condition ofhigh temperature; the reaction mechanism of 4 systems were roughlysame, but the catalysts can accelerate the curing of the resins and decreasethe curing temperature. Epoxy/glass cloth blend was modified by hollow glass bead, addingSurfactant and cyanate into the blend in additional. The relationship - III -北 京 化 工 大 学 硕 士 学 位 论 文between the micro-morphology and the mechanical properties ,thethermal properties and water absorption of epoxy /glass cloth/hollowglass-bead blend were studied systematically. The results showed that,using hollow glass-beads as filler improved the mechanical properties andthe thermal properties of epoxy/glass cloth blend. Especially, usingsmaller Size of glass-Beads, treating surface of glass-Bead with thecoupling agent and adding Surfactant into the blend obtained theoptimum results. In this state, the mechanical properties and the thermalproperties of blend were improved with the increase of the glass-beadcontent. The thermal expansion coefficient of material was decreasedgreatly when add cyanate into the blend of epoxy/glass cloth/ hollowglass-bead.Adding a few glass-bead into epoxy/glass cloth blenddecreases the water-absorption of it. However, with the increase of theglass-bead content, the water-absorption of blend decreases. AfterSurfactant was added, this trend became not remarkable.