Structural epoxy adhesive was investigated for its thermal stability and degradation behaviour in a thermo-oxidative environment by thermogravimetry analysis (TGA). Non-isothermal TGA was performed at temperatures between 30 and 600°C utilizing different heating rates. The ageing characteristics of material were determined by an accelerated ageing study using isothermal TGA at different temperatures for 5% threshold conversion. The activation energies from both non-isothermal TGA and isothermal TGA were estimated and the activation energy values for 5% degradation from both the methods were in good agreement. The epoxy adhesive with titanium dioxide as filler showed a shelf life exceeding 13 years at ambient conditions (27°C). Additionally, the lap shear strength of the adhesive joint was also tested after treating the samples at 70°C with 90% relative humidity to evaluate the hydrothermal effect on adhesive joint.

中文翻译：

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高温应用热重分析对环氧胶粘剂热稳定性和寿命估算的研究

通过热重分析 (TGA) 研究了结构环氧树脂胶粘剂在热氧化环境中的热稳定性和降解行为。非等温 TGA 在 30 到 600°C 之间的温度下使用不同的加热速率进行。材料的老化特性是通过使用等温 TGA 在不同温度下进行 5% 阈值转换的加速老化研究来确定的。估计了非等温 TGA 和等温 TGA 的活化能，两种方法的 5% 降解的活化能值非常一致。以二氧化钛为填料的环氧粘合剂在环境条件 (27°C) 下的保质期超过 13 年。此外，