| A type of resin containing epoxy-vinylester multifunctional oligomers was synthesized using N,N,N’,N’-tetraglycidyl-4,4’-diaminodiphenyl methane (TGDDM) and acrylic acid (AA) as raw materials at molar ratio (TGDDM/AA=1:2). Acid value and epoxy value were tested in the reaction of TGDDM and AA. The acid value was 0 and the epoxy value reduced to half of the initial value at the end of reaction, it showed that AA was run out and half of epoxy group was remained. FT-IR and 1H-NMR characterization showed that the characteristic peak of C=C double bond was dispeared, the characteristic peak of epoxy group weakened and the characteristic peak of hydroxy and ester group appeared. It proved that MEVO was synthesized by the reaction of TGDDM and AA.Curing reaction of MEVO resin was investigated by DSC and the effection to MEVO curing process by adding methyl ethyl ketone peroxide (MEKP) and methyl tetrahydrophthalic anhydride (MeTHPA) was studied. There was one curing exothermic peak corresponding to vinyl ester/styrene free radical polymerization in MEVO-MEKP system.There was also one curing exothermic peak corresponding to epoxy group ring opening polymerization,but vinylester/styrene thermal polymerized for the heat of epxoy ring opening and temperature programming.Threre were two curing exothermic peaks corresponding to vinylester/styrene freeradical polymerization and epoxy group ring opening polymerization respectively.The result showed that two kinds of curing recation affect each for the two peaks were overlap.Properties of MEVO casting were investigated by DSC, TGA, SEM and mechanical testing. The result showed that MEVO mechanical properties were improved relative to TGDDM, the impact strength increased by more than 100%. MEVO glass-transition temperature was 178℃ and the thermostability was reduced compared to TGDDM. MEVO was still a type of high temperature resistant resin. |
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