1-己基-3-甲基咪唑四氯化铁盐固化环氧树脂E-51的反应特性

采用差示扫描(DSC)量热分析法研究了1-己基-3-甲基咪唑四氯化铁离子液体(C₆mim]FeCl₄)与双酚A型环氧树脂E-51的固化反应。结果显示,由于C₆mim]FeCl₄包含多级胺基结构,因此可以作为E-51的高温固化剂使用,其与E-51的反应包含两个阶段:第一个阶段的反应放热峰峰顶温度约在120 ℃,第二个阶段的反应放热峰峰顶温度会随着C₆mim]FeCl₄用量的增加而发生变化。当C₆mim]FeCl₄与混合胺复配成新型固化剂时,二者产生明显的协同效应。通过恒温DSC实验发现,复配体系与E-51的固化反应可以在室温下发生,表现为在30 ℃固化反应放热峰峰顶放热时间为5 min左右,且随着恒温固化反应温度的提高,峰顶放热峰时间会缩短。非等温动力学结果显示:复配体系与E-51的反应活化能为979 J/mol,仅是混合胺体系的17%左右。反应级数为0.5表明这一固化反应是无规反应。

Reaction Characteristics of Epoxy Resins E-51 Cured by 1-Hexyl-3-Methyl Imidazole Iron Tetrachloride Salt

Here we investigated the curing reaction between bisphenol epoxy resin E-51 and 1-hexyl-3- methylimidazole iron tetrachloride salt(C₆mim]FeCl₄) by differential scanning calorimetry. It was confirmed that the multi-level amine structure makes C₆mim]FeCl₄ possible to be used as high-temperature curing agent for E-51. The curing reaction can be divided into two stages:at the first stage, the exothermic peak is about 120 ℃; at the second stage, the exothermic peak changes with the volume of C₆mim]FeCl₄. When C₆mim]FeCl₄ reacts with the mixed-amine to form a new curing agent, they exhibit apparent synergistic effect. The DSC results show that the new curing agent can react with E-51 under room temperature. The duration of exothermic peak is about 5 min at 30 ℃, and moreover, the duration decreases with the increasing temperature. The activation energy of the reaction calculated by the method of non-isothermal kinetics is 979 J/mol, which is only about 17% of the mixed-amine system. Finally, as the reaction order of the curing reaction is 0.5, it is believed to be a kind of random reaction.