通过快速扫描热量计揭示了由可逆胺键交叉连接的分支多糖醇网络中的玻璃体行为
Vasiliki Maria Stavropoulou1,2, Marta Aldecoa-Ortueta1,2, Ester Verde-Sesto1,3
1Materials Physics Center (CFM-MPC), CSIC-UPV/EHU, Paseo Manuel Lardizábal 5, 20018 Donostia-San Sebastián, Spain.
Macromolecules
|March 2, 2026
概括
基于胺的玻璃剂提供了可重加工性. 这项研究区分了传统的玻璃转换和使用快速扫描热量计的多糖醇网络的玻璃转换,揭示了不同的热事件.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 超分子化学 超分子化学
背景情况:
- 动态共价键,特别是胺键,对于玻璃化物发展至关重要,使材料重新排列和再加工成为可能.
- 玻璃体通过改变它们的交联化学物质,表现出可调节的特性,例如玻璃过渡温度 (Tg).
- 与β-ketoester (PG-βkest) 功能化的多糖醇 (PG) 作为创建新型聚合物网络的多功能平台.
研究的目的:
- 通过使用不同的二胺来研究胺-交叉链接的多糖醇网络的热行为.
- 在这些聚合物网络中区分传统的玻璃转换和玻璃转换.
- 阐明控制玻璃体系统中热事件的基本机制.
主要方法:
- 合成β-基托功能化的分支多糖醇 (PG-βkest).
- 将PG-βkest与三种不同的二胺进行交叉链接:二氨基 (DAP),2.2'-(乙烯二氧化物) -bis-(乙烯胺) (EDO),以及杰夫胺D230 (Jeff).
- 使用常规差分扫描热量计 (DSC) 和快速扫描热量计 (FSC) 的热量分析,加热/冷却速率高达1000 Ks-1.1.
- 基辛格分析以确定热事件的明显激活能量.
主要成果:
- 所有测试的聚合物网络都表现出胺键形成和可调节的玻璃过渡温度.
- 传统的DSC显示了所有网络的单一,广泛的特定热步骤.
- 快速扫描热量计 (FSC) 成功解决了杰法胺D230交联网络中的两个不同的热事件.
- 基辛格分析提供了激活能量,证实了高温事件作为玻璃变化 (Tv),低温事件作为常规玻璃过渡.
结论:
- 快速扫描热量计对于剖析玻璃体系统中复杂的热行为至关重要.
- 这项研究提供了令人信服的证据,证明了传统玻璃过渡和基于多糖醇的玻璃制剂中的玻璃制剂转换的共存.
- 这项研究有助于更好地理解玻璃材料动力学及其对先进材料应用的潜力.
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