通过结合Arrhenius和时间-温度叠加 (TTS) 推断,证明EPDM的非Arrhenius行为
Zhiguo Cui1, Wensong Liu2, Lei Tan1
1CRRC Qingdao Sifang Co., Ltd Qingdao 266111 China.
RSC advances
|February 12, 2024
概括
这项研究揭示了乙烯二烯单体 (EPDM) 表现出非Arrhenius行为,这对于准确的寿命预测至关重要. 结合Arrhenius和时间-温度叠加推断的新方法证明了这种行为,并确定了激活能量.
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:
- 精确预测乙烯二烯单体 (EPDM) 的寿命对于可靠的性能和避免低效的加速老化实验至关重要.
- 了解聚合物的非Arrhenius行为对于推断不同温度的降解数据至关重要.
- 穆尼-里夫林方程是分析聚合物网络行为的常见工具.
研究的目的:
- 为了研究EPDM在加快热老化过程中的非Arrhenius行为.
- 分析老化温度和时间对有效交联密度的影响.
- 开发一种用于证明非Arrhenius行为和确定激活能量的新方法.
主要方法:
- 在70°C至130°C的温度下进行了EPDM的加快热老化.
- 系统地测试了老化的EPDM的拉伸特性.
- 应用了Mooney-Rivlin方程来评估交叉连接密度的变化.
- 一种联合的阿雷尼乌斯和时间-温度叠加 (TTS) 推断方法被开发和使用.
主要成果:
- 随着老化温度接近115°C,观察到物理交联密度的显著增加,这表明激活能量的变化.
- 该研究成功地证明了EPDM的非Arrhenius行为,使用拟议的组合取值技术.
- 有效的交叉连接密度与老化温度和时间相关.
结论:
- EPDM表现出非Arrhenius行为,这意味着其降解率在所有温度中不是恒定的.
- 开发的方法提供了一种可靠的方法来证明非Arrhenius行为,并确定高温和低温处理的激活能量.
- 这项研究有助于更准确的寿命预测和优化EPDM的实验设计.
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