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Updated: May 7, 2025

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生物基聚聚 ((乙烯2,5-酸) (PEF) 的相图,玻璃动力学和结晶动力学

Ioannis Tzourtzouklis¹, Panagiotis Kardasis¹, George Z Papageorgiou^2,3

¹Department οf Physics, University οf Ioannina, Ioannina 45110, Greece.

|January 1, 2025

概括

本研究绘制了聚乙烯2,5-酸 (PEF) 的压力-温度相图,揭示了压力如何影响其玻璃和结晶温度. 压力影响子玻璃动态和结晶动态,为PEF提供了关于PEF的见解.

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
物理化学物理化学

背景情况:

像聚乙烯2,5-酸 (PEF) 这样的生物基聚烯是石油基塑料的可持续替代品.
在不同条件下了解PEF的相态度和结晶动力学对于其应用开发至关重要.

研究的目的:

要构建PEF的压力-温度 (P-T) 阶段图.
为了研究亚玻璃动力学和压力下的结晶动力学的分子起源.
探索压力对PEF热和动态特性的影响.

主要方法:

介电光谱 (DS) 是温度和压力的函数.
差异扫描热度计 (DSC) 用于热力学分析.
同时微角 (SAXS) 和广角 (WAXS) 的X射线散射用于结构分析.

主要成果:

PEF 的 P-T 阶段图包括玻璃,灭融,晶体和正常融阶段.
冷结晶温度 (Tcc) 与压力线性增加,而玻璃过渡温度 (Tg) 显示出更强的压力依赖.
压力使细分过程变密,但阻碍了亚玻璃β过程,可能影响气体屏障特性.
结晶动力学遵循不同探头的西格形 (Avrami-type) 行为,在受限无形分数 (RAF) 形成之前观察到一个初始的中形相.

结论:

PEF表现出不同的阶段和压力依赖的热过渡.
压力在调节PEF的动态和结晶路径方面发挥着重要作用.
该研究确定了保持PEF在转移稳定的灭无形状态的途径,这与加工和应用有关.

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