重组含有低稳定性的晶体的聚乙烯糖酸
Katalee Jariyavidyanont1, Christoph Schick2, René Androsch1
1Interdisciplinary Center for Transfer-Oriented Research in Natural Sciences (IWE TFN), Martin Luther University Halle-Wittenberg, 06099, Halle/Saale, Germany.
Macromolecular rapid communications
|June 14, 2024
概括
聚乙烯酸 (PBS) 晶体在缓慢加热时重新组织. 在70°C以下,只有微小的结构改进才会发生;较高的温度会导致融化和再结晶,从而提高晶体的完美性.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
- 晶体学 晶体学是指结晶学.
背景情况:
- 聚乙烯酸 (PBS) 是一种可生物降解的聚,以其半晶性而闻名.
- 了解PBS的热行为和结构演变对于其应用和加工至关重要.
- 在融化结晶过程中,高超冷却会导致具有低点的小,不完美的PBS晶体.
研究的目的:
- 为了研究半晶体聚乙酸 (PBS) 在缓慢加热时的重组行为.
- 在热处理过程中分析结晶性,晶体大小和晶体完美的变化.
- 在PBS中阐明晶体结构演化的机制.
主要方法:
- 差分扫描热量计 (DSC) 用于热分析.
- 温度分辨率的X射线散射技术用于结构分析.
- 在化结晶的PBS样本上进行了受控的缓慢加热实验.
主要成果:
- 在20°C形成的晶体表现出有限的重组和不变的不完美,直至70-80°C.
- 高于70-80°C的加热会触发DSC的外热峰值,这表明结构发生了重大变化.
- 较高的温度导致更大,更完美的晶体形成,在100°C左右融化,通过化再结晶.
结论:
- PBS晶体的低温重组受到限制,只允许微小的结构改进.
- 在PBS中,显著的晶体完美化和加厚是通过化和随后的化再结晶发生的,而不是固态加厚.
- 完整的融化和叶片重新排列是PBS实质性的结构演变所必需的.
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