过载对交联聚乙烯铜线的热分解动力学的影响
Yizhuo Jia1, Pengrui Man1, Xinyao Guo1
1Forensic Science Institute, China People's Police University, Langfang 065000, China.
Polymers
|October 14, 2023
概括
过载交联聚乙烯 (XLPE) 电线绝缘材料的分解速度更快,温度更低. 这一发现对于改进使用XLPE绝缘材料的电气系统的防火策略至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
- 消防安全工程 消防安全工程
背景情况:
- 充电电线中的过载故障可能会由于热量而改变绝缘材料结构.
- 了解电线绝缘的热分解动力学对于预防和控制火灾至关重要.
研究的目的:
- 为了研究新的和过载的交联聚乙烯 (XLPE) 铜线的热分解.
- 为了确定过载对XLPE绝缘材料的热分解动力学和机制的影响.
主要方法:
- 热重力测量 - 里埃变换红外光谱学 (TG-FTIR)
- 圆热量计 圆热量计
主要成果:
- 过载的XLPE绝缘材料显示热分解开始温度 (~15K) 和激活能量 (~20kJ mol-1) 降低.
- 反应机制从D-ZLT3转移到A2 (0 < α < 0.5).反应机制从D-ZLT3转移到A2 (0 < α < 0.5).反应机制从D-ZLT3转移到A2 (0 < α < 0.5).
- FTIR分析确定了主要的热解产物,包括C-H拉伸,H2O,CO2,C-H剪刀振动和C=O/C=C拉伸.
结论:
- 过载严重影响XLPE绝缘材料的热稳定性和分解路径.
- 该研究提供了关键数据,以加强XLPE电线的电气应用中的消防安全措施.
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