衰老过程条件对聚 (二甲) 基 каучук的热性能的影响
Anna Morawska-Chochół1, Magdalena Szumera2, Andrzej Młyniec3
1Department of Biomaterials and Composites, Faculty of Materials Science and Ceramics, AGH University of Krakow, al. Mickiewicza 30, 30-059 Krakow, Poland.
Materials (Basel, Switzerland)
|November 27, 2024
概括
即使在机械负荷下,在高温下老化的 (聚二甲基) 也提高了它们的热稳定性. 这项研究没有发现降解,表明在临界温度附近的性能有所改善.
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:
- 类,特别是聚二甲基 (PDMS),是重要的工业弹性体,特别是用于包装材料等高温应用.
- 机械应力和高温可以在服务期间改变弹性体的结构和热特性.
- 了解衰老机制对于确保PDMS组件在苛刻环境中的可靠性能至关重要.
研究的目的:
- 为了全面评估商业的老化过程ELASTOSIL® LR 3842/50 A/B.
- 用先进的分析技术研究热老化和机械负荷引起的结构变化.
- 确定老化条件对PDMS的热稳定性和降解行为的影响.
主要方法:
- 热分析 (例如TGA,DSC) 与质谱学相结合.
- 用X射线衍射 (XRD) 和红外光谱 (FTIR) 进行结构分析.
- 在125°C和175°C的PDMS样品的受控老化,带有和没有11公斤的负载.
主要成果:
- 在高温下老化PDMS,特别是在175°C的负载下,显著提高了其热稳定性.
- 结构分析显示,二次交叉连接和后固化,而不是降解,是衰老的主要结果.
- 没有发现聚合物降解的证据,即使在接近制造商推的极限 (180°C) 的温度下也是如此.
结论:
- 衰老过程,特别是在热和机械应力的联合下,增强了ELASTOSIL® LR 3842/50 A/B的热稳定性.
- 由于其临界服务温度附近的二次交叉连接而不是降解,PDMS表现出弹性和更好的高温性能.
- 这些发现支持在高温应用中扩大这种的使用范围,甚至接近180°C,而不需要立即使用额外的稳定剂.
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