室温潜伏性中温固化环氧树脂体系的制备与性能

将自制咪唑衍生物EGE-2MI作为双氰胺-环氧树脂体系的促进剂,研究了其固化过程及室温储存性能。采用DSC法研究了该环氧树脂体系的固化反应动力学,确定了其最佳固化工艺参数;通过DSC测试室温存放不同时间后该环氧树脂体系的热焓值变化来确定其室温存储期;并测试了其中温固化产物的力学性能。结果表明:EGE-2MI质量比为0.6%~1.8%(环氧树脂为100%)的双氰胺-环氧树脂体系可以满足115~125℃固化,在室温下可以存放35天以上,EGE-2MI质量分数为1.8%时,该环氧树脂体系的活化能为87.23kJ/mol;固化后产物的铝-铝搭接剪切强度达到21.3 MPa,浇注体的室温拉伸强度在40 MPa以上。

Preparation and properties of latent moderate-temperature curing epoxy resin system

Using a novel imidazole derivative EGE-2MI as latent accelerant for dicyandiamide-epoxy resin system, the curing behavior and the storage life of the system were investigated.The kinetics of curing reaction of the resin system were studied by DSC method,and optimum curing process parameters were determined.The storage life of the dicyandiamide-epoxy resin system at room temperature was evaluated by using DSC to measure the variation of the enthalpy at different storage time in ambient environment.And mechanical properties of the moderate-tempera-ture curing products were also tested and analyzed.The results reveal that the dicyandiamide-epoxy resin systems with 0.6%-1.8% EGE-2MI content (content of epoxy resin as 100%)can be effectively cured at 115-125℃,the cu-ring reaction activation energy of the resin system with 1.8% EGE-2MI content is 87.23 kJ/mol.The resin system is also chemically stable at room temperature,and has a storage life for over 35 days.Al-Al shear strength of cured system can reach 21.3 MPa,and its tensile strength is over 40 MPa.