摘要
为研究长期热老化对聚酰亚胺材料性能的影响,分别在280、315、350℃下对其进行加速热老化试验,通过材料力学性能的变化分析热作用对材料宏观特性的影响,并结合X射线衍射(XRD)测试和扫描电镜(SEM)从微观角度进行表征。结果表明:在长期热老化下,聚酰亚胺的力学性能变化明显,整体呈下降趋势,且温度越高,下降速度越快。XRD数据表明在热老化的长期作用下聚酰亚胺内部分子链间距离增大,有序性降低。扫描电镜结果表明老化后试样表面出现缺陷和孔洞等。以力学性能变化与温度和时间的关系为依据,结合Arrhenius方程建立寿命模型,该模型具有很好的相关度。
In order to explore the effect of long-term thermal ageing on the insulating properties of poly- imide, accelerated thermal ageing tests were conducted on polyimide at 280, 315, 350 ℃. The impacts of thermal effects on the properties of polyimide were analyzed and chracterized by XRD and SEM. The re- suits show that the mechanical properties decrease obviously under the long-term thermal ageing, and the higher the temperature, the faster the decrease rate is. The XRD indicates that after long-term thermal ageing, the space between polyimide internal molecular chain increases, and the order of molecular chain decreases. The SEM indicates that there are defects and holes on the surface of samples after ageing. According to the relationship between mechanical properties change and temperature and time, a life mod- el is established combined with Al-rhenius equation, and the model has good correlation coefficient.
出处
《绝缘材料》
CAS
北大核心
2017年第7期31-35,共5页
Insulating Materials
基金
国家电网公司科技项目
关键词
聚酰亚胺
力学性能
热老化
表面形貌
寿命模型
polyimide
mechanical properties
thermal ageing
surface morphology
life model
