生物基聚合物的结晶控制结构和热性质 (乙烯2,5-二碳酸盐)
Miroslaw Pluta1, Joanna Bojda1, Mariia Svyntkivska1
1Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland.
Polymers
|November 9, 2024
概括
冷结晶温度显著影响生物基聚乙烯2,5-氨基碳酸盐 (PEF) 的结构和热性能. 控制这种温度会影响晶相,晶度和热稳定性,这对于PEF材料的应用至关重要.
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
- 生物材料是一种生物材料.
背景情况:
- 生物基聚合物为以石油为基础的塑料提供可持续的替代品.
- 聚乙烯2,5-基碳酸盐 (PEF) 是一个有前途的生物基聚,在包装和织品中具有潜在的应用.
- 了解PEF的结构-属性关系对于优化其性能至关重要.
研究的目的:
- 研究冷结晶温度 (Tc) 对生物基PEF的结构和热特性的影响.
- 阐明PEF中复杂的融化行为和晶相过渡.
- 在不同的结晶条件下将形态特征与热行为相关联.
主要方法:
- 差分扫描热量计 (DSC) 用于分析结晶和融化行为.
- 扫描电子显微镜 (SEM) 检查形态.
- 分析晶相 (α'-和α-相) 和刚性无形相含量.
主要成果:
- 冷结晶温度 (Tc) 决定了PEF的晶体结构和热特性.
- PEF表现出复杂的融化行为,具有两个不同的晶体群体 (不稳定和稳定).
- 较低的Tc有利于α'-阶段,较低的结晶度和更高的刚性无形含量,而较高的Tc则促进α-阶段,更高的结晶度和潜在的轻微降解.
结论:
- 冷结晶温度是控制PEF的热特性和形态学的关键参数.
- 通过调整结晶条件,可以调整PEF的热行为,从而有可能提高热稳定性.
- SEM揭示了带有板状结构的球形形态,表明PEF矩阵内的有序晶体安排.
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