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采用2-甲基咪唑盐(2MZS)作为环氧树脂/酸酐固化体系的潜伏性促进剂,以延长产品适用期.采用贮存稳定性试验和凝胶时间测试确认了2MZS在双酚A环氧树脂(E51)/甲基纳迪克酸酐(MNA)固化体系中的潜伏性促进作用.通过差示扫描量热仪(DSC)考查了E51/MNA/2-甲基咪唑(2MZ)体系和E51/MNA/2MZS潜伏性体系的非等温固化过程,并对体系的固化动力学进行分析.最后对固化产物的热稳定性及电性能进行了测试.结果表明:由Kissinger和Ozawa模型得到的E51/MNA/MZS体系的表观活化能(Ea)分别为70.88 kJ/mol和78.36 kJ/mol,均大于E51/MNA/MZ体系的Ea(59.82 kJ/mol和67.32 kJ/mol).在某一临界温度以下,E51/MNA/2MZS体系的固化反应速率常数(k')低于E51/MNA/2MZ体系;而高于该温度时,E51/MNA/2MZS体系的k'值高于E51/MNA/2MZ体系.这些结果说明2MZS对于E51/MNA体系的固化具有潜伏性促进作用,且E51/MNA/2MZS固化物的热稳定性及热态电性能均优于E51/MNA/2MZ体系.

2-methylimidazole salt (2MZS) was used as a latent accelerator of epoxy resin/anhydride curing system to prolong the pot life of product.The latent accelerating effects of 2MZS in bisphenol A epoxy resin (E51)/methyl nadic anhydride (MNA) curing system was confirmed by storage stability experiment and gelation time test.The non-isothermal curing processes of E51/MNA/2MZ and E51/MNA/2MZS systems were investigated by DSC,and their curing kinetics were analyzed.Finally,the thermal stability and electrical properties of the curing products were tested.The results show that the apparent activation energy (Ea) of the E51/MNA/2MZS system obtained by the Kissinger and Ozawa models is 70.88 kJ/mol and 78.36 kJ/mol respectively,which are higher than those of the E51/MNA/MZ system (59.82 kJ/mol and 67.32 kJ/mol).The curing raction rate constant (k') of the E51/MNA/2MZS system is lower than that of the E51/MNA/2MZ system below certain critical temperature,and above this temperature the k'of E51/ MNA/2MZS system is higher than that of E51/MNA/2MZ system.These results indicate that 2MZS has latent accelerating effects on the curing of E51/MNA system,and the thermal stability and electrical properties at high temperature of the E51/MNA/2MZS curing products are better than that of the E51/MNA/ 2MZ system.