以新型离子液体3-（2-氨基-2-氧乙基）-1-丁基咪唑二氰胺盐（AOBD）作为双酚A型环氧树脂（E-51）的固化剂，深入研究其固化工艺和固化物的性能。结果表明：AOBD可用作E-51的高温固化剂，二者最佳配比为AOBD/E51=10：100，最佳固化温度范围为122~156℃，后固化温度为178℃。固化后E-51浇注体的拉伸强度为30.7 MPa，拉伸模量为3 233.1 MPa，断裂伸长率为1.1%，热分解温度为414.0℃。动态力学分析表明，浇注体的最大损耗因子为0.56，玻璃化转变温度为174.8℃，贮存模量为134.8 MPa，交联密度为3 198.9 mol·m-3。红外光谱测试表明AOBD的固化反应包括两个阶段，首先-CONH2在低温下与环氧基团发生开环反应，然后阴离子与环氧基在高温下进一步反应提高交联密度。
In this work, ionic liquids of 3-(2-amino-2-oxoethyl)-1-butyl imidazolium dicyanamide (AOBD) was used as curing agent for bisphenol A epoxy resin (E-51). The curing processes and the thermoset properties of AOBD/E-51 were fully characterized. Results show that AOBD is a high temperature curing agent for E-51, the optimum curing ratio and temperature range of AOBD/E-51 are 10:100 and 122-156℃, respectively, and the post-curing temperature is 178℃. The mechanical properties of the thermosets were characterized as follows. The tensile strength is 30.7 MPa, the tensile modulus is 3 233.1 MPa, and the elongation at break is 1.1%. The dynamic mechanical thermal analysis results show that the maximum loss factor, the glass transition temperature, the storage modulus, and the crosslinking density are 0.56, 174.8℃, 134.8 MPa, and 3 198.8 mol·m-3, respectively. Based on the IR spectra in different curing processes, the -CONH2 groups of AOBD react with epoxy groups at lower temperature, and then the anions react with epoxy groups further at higher temperature to achieve the whole curing processes. This study provides informative guidelines for choosing new curing agents of epoxy resin.
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