The differential thermal-thermo-synchronous analyzer was used to study the thermal stability of CYCOM 970 epoxy composites, including the weight loss temperature and weight loss rules of blocky and powdered carbon fiber epoxy composites at different heating rates (10, 20, 30, 40 ℃/min). The research conclusion showed that with the increase of heating rate, the initial decomposition temperature, reaction final temperature and maximum weight loss rate temperature of the powdered and blocky experimental samples all moved towards high temperature. At the same time, the pyrolysis temperature range gradually expanded, and the mass loss obviously increased. Furthermore, the differential and integral methods were used to calculate the pyrolysis kinetics related parameters of the powdered and blocky experimental samples.The calculation results indicated that for the powdered experimental samples, the overall activation energy only changed a little, which demonstrated its uniform pyrolysis and stability of pyrolytic reaction.However, the activation energy of the blocky experimental samples was relatively high at the initial stage, and then stabilized gradually later because of the blocky structure being stable and not easy to decompose.Especially, the results of experiments and calculations manifested that the thermal stability of the blocky experimental samples was better than that of the powdered experimental samples at the same heating rate as well.%利用差热—热重同步分析仪研究CYCOM 970环氧树脂复合材料的热稳定性,在升温速率为10、20、30、40℃/min条件下对块状、粉状碳纤维环氧复合材料的失重温度和失重规律进行研究.研究结论表明,随着升温速率的增加,粉状和块状实验样品在每个阶段的初始分解温度、反应最终温度及最大失重速率温度均向高温方向移动,热解温度范围逐渐扩大,质量损失明显增加.运用微分法和积分法进行热解动力学相关参数计算,结果表明:粉状实验样品活化能值变化不大,说明其热解均匀,热解反应比较稳定;而块状实验样品因结构稳定、不易分解,初始阶段活化能值较高,后期逐渐稳定.相同升温速率下,块状实验样品的热稳定性均高于粉状实验样品.
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