关于PMR350树脂热氧衰老特征和降解动力学的研究
Yadan Wu1, Wenchen Zhao1, Yang Liu1
1Science and Technology on Advanced Ceramic Fibers and Composites Laboratory, College of Aerospace Science and Engineering, National University of Defense Technology, Changsha 410073, China.
Polymers
|September 28, 2024
概括
这项研究显示,烯覆盖的聚胺预聚合物 (PMR350) 具有优越的热稳定性和耐老化性能. 在长时间暴露在高温下后,PMR350保持其性能,在苛刻的环境中表现出色.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 聚胺在高温应用中至关重要,但其热稳定性和老化动力学需要进一步研究.
- 烯覆盖聚胺预聚合物 (PMR350) 是一种新型材料,具有提高热性能的潜力.
- 关于PMR350.的热衰老和降解动力学的数据有限.
研究的目的:
- 系统地研究PMR350.的热氧化稳定性和热降解动力学.
- 分析不同大气层 (空气与) 对PMR350热行为的影响.
- 为工程应用提供PMR350的热稳定机制的理论见解.
主要方法:
- 热重力测量分析 (TGA) 用于评估热分解温度和降解速度.
- 进行了同热氧化衰老实验,以评估在持续的热应激下减肥的情况.
- 使用先进的动力分析方法,包括弗林-沃尔-奥扎瓦,基辛格-阿卡希拉-苏诺斯和弗里德曼,以确定降解激活能量和反应模型.
主要成果:
- PMR350在中显示出更高的5%热分解温度 (Td5%) (比空气高29°C),并且在中显著降低了最大降解率.
- 在空气下的热降解发生在一个阶段,激活能量为~57kJ/mol,按照F2反应模型.
- 的降解分为两个阶段,具有更高的激活能 (240 kJ/mol和200 kJ/mol),对应于A2和D3模型. 在350°C老化300小时后,PMR350保持了高硬度和高模量.
结论:
- PMR350表现出极好的耐热和氧化老化性能,超过了高温聚合物应用的预期.
- 氧气显著加速PMR350的热降解,突出了大气条件的重要性.
- 该研究为PMR350在需要高热稳定性的环境中应用提供了关键数据和理论理解.
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