脱聚合基塑化如何影响聚 (P-Dioxanone) 中冷结晶的过程
Roman Svoboda1, Jana Machotová2
1Department of Physical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentská 573, Pardubice, 53210, Czech Republic.
Macromolecular rapid communications
|June 26, 2024
概括
150°C以上的p-dioxanone的自塑化显著改变了其结晶和热特性. 这一过程影响了聚合物链的移动性,晶体的生长和机械特性.
科学领域:
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
- 结晶研究 结晶研究
背景情况:
- 自塑化,通过单体纳入增加聚合物链的流动性,影响聚合物的特性.
- 聚二氧化 (PDX) 是一种聚合物,其结构,热和机械特性可以通过自我塑化而受到影响.
研究的目的:
- 调查热诱导的自我塑性化对聚二氧化结晶的影响.
- 分析由于自我塑化而导致的晶体生长从无形和化状态的变化.
主要方法:
- 不同扫描热量计 (DSC)
- 光学显微镜和拉曼显微镜
- 热力学分析 (TMA) 是一种方法.
- 使用多角度光散射 (SEC-MALS) 进行尺寸排除色谱.
- 进行X射线衍射分析 (XRD).
主要成果:
- 在150°C以上 (脱聚合温度) 观察到PDX结晶和机械性质的显著变化.
- 强烈的自我塑化降低了结晶温度,增加了晶体生长率,消除了多态过渡,降低了化温度.
- 自塑化并没有显著改变结晶体的大小,定位或形态,这些主要取决于晶体生长温度.
结论:
- 在高于150°C的温度下,热诱导的自我塑化会对PDX结晶行为和热性能产生深远的影响.
- 该研究讨论了可变激活能概念在观察到的结晶数据中的表现.
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