自核化使热塑性聚氨中的多态选择成为可能
Zakarya Baouch1, Leire Sangroniz2, Yunxiang Shi2
1Department of Chemistry and Industrial Chemistry, University of Genoa, Via Dodecaneso 31, 16146 Genoa, Italy.
Macromolecules
|March 2, 2026
概括
热塑性聚氨 (TPU) 的自我核化控制了晶体的形成. 这一过程加速了结晶,并有利于更有序的II形式,即使在通常无法形成它的组合中.
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
- 结晶化 结晶化 结晶化
背景情况:
- 热塑性聚氨 (TPU) 具有复杂的结晶行为.
- 在TPU中的多态性,特别是形式I和形式II,影响材料特性.
- 控制多态结果对于定制TPU性能至关重要.
研究的目的:
- 研究自我核化对TPU多态结晶的影响.
- 确定自我核化如何影响结晶动力学和不同硬段 (HS) 内容的结晶结果.
- 阐明自我核化诱导特定多态体形成的机制.
主要方法:
- 差分扫描热量计 (DSC) 用于监测热过渡和结晶.
- 现场广角X射线衍射 (WAXD) 用于结构分析.
- 极化光光学显微镜 (PLOM) 用于可视化晶体形态.
主要成果:
- 自核化显著改变TPU结晶,加速动力学并促进II形式的形成.
- 确定了一个独特的自我核化域 (Domain II),影响了多态选择.
- 即使是含有低HS的TPU,通常只形成I型,也被诱导通过自我核化在II型中结晶.
- 在化物中介尿之间的键的持久性被提出为Form II偏好的原因.
结论:
- 自核化在广泛的组成范围内对TPU多态选择提供了精确的控制.
- 这种热处理策略使得更有序的Form II多态分子能够形成,即使在具有挑战性的组合中也是如此.
- 自核化提供了一种多功能方法,通过受控的热处理来定制TPU材料特性.
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