有没有一个具有高玻璃过渡温度的玻璃化器? 一个关于刚性聚化物与动态结交联的案例研究
Yueh-Hsin Wang1, Du-Yuan Hung1, Ying-Ling Liu1
1Department of Chemical Engineering, National Tsing Hua University, No. 101, Sec. 2, Kuang-Fu Road, Hsinchu, 300044, Taiwan.
Macromolecular rapid communications
|June 11, 2024
概括
高玻璃过渡温度 (Tg) 玻璃制品需要更高的加工温度来缓解压力和可回收. 高温可以引起副作用,影响回收材料的性能,突出显示扩散控制的挑战.
科学领域:
- 聚合物科学与工程 聚合物科学与工程
- 材料化学 材料化学
背景情况:
- 玻璃聚合物是具有适应性网络的交联聚合物,结合了可性和可回收性.
- 它们的动态行为取决于玻璃过渡温度 (Tg) 和债券交换率 (Tv).
研究的目的:
- 为了研究高Tg对压力放松和玻璃剂的物理可回收性的影响.
- 作为模型系统,使用具有动态结的高Tg聚胺.
主要方法:
- 研究了聚胺玻璃体在不同温度相对于其Tg的压力放松行为.
- 在加工条件下评估物理可性和可回收性.
- 在回收和再加工过程中检查了潜在的副作用.
主要成果:
- 聚胺玻璃体在其Tg (310°C) 以上10°C时显示出有限的应力放松.
- 显著的应力松 (3300秒) 和可塑性在345°C时实现.
- 恶劣的回收条件 (高温/高压) 可能导致副作用,改变热性能.
结论:
- 高Tg需要更高的加工温度,以提高玻璃材料的可性和可回收性.
- 扩散控制对于高Tg玻璃体的拓过渡至关重要.
- 存在一个Tg的天花板,这对未来的玻璃体开发构成了挑战.
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