在高Tg,低晶度电纤维中对方向和结晶性的拉曼分析
Arnaud W Laramée1, Christian Pellerin1
1Département de chimie, Université de Montréal, Montréal, QC, Canada.
Applied spectroscopy
|September 29, 2023
概括
在电过程中控制溶剂蒸发,可以增强聚合物纤维的分子导向. 更快的蒸发增加了有效的玻璃过渡温度,为先进的应用提供更好的纤维特性.
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
- 纳米技术 纳米技术
背景情况:
- 电纤维往往缺乏足够的分子导向,限制了它们的性能.
- 在电旋过程中喷射刚性对于实现分子对齐至关重要.
- 溶剂蒸发速度显著影响喷气刚性和纤维特性.
研究的目的:
- 开发定量拉曼方法来评估电聚合物纤维中的分子方向和结晶性.
- 调查溶剂挥发性对纤维分子方向和结晶性的影响.
- 为了确定有效的玻璃过渡温度和电过程中的分子方向之间的关系.
主要方法:
- 使用定量拉曼光谱法测量分子方向和结晶性.
- 通过电制造各种直径的多2,6-二甲基-1,4-氧化物) 纤维.
- 用不同的挥发率的溶剂生产纤维,以控制蒸发速度.
主要成果:
- 溶剂挥发率通过影响有效的玻璃过渡温度 (Tg,eff) 直接调节分子方向和结晶性.
- 高挥发性溶剂导致显著更高和更持续的分子导向 (纤维<1.0μm的中位数P2为0.53).
- 由于溶剂的快速蒸发,早期喷气玻璃化促进了定向无形相和中度应变诱导的结晶.
结论:
- 利用溶剂挥发性是提高电纤维分子定向的关键策略.
- 高玻璃过渡温度 (Tg) 对于在无形或低晶度聚合物中实现高分子定向至关重要.
- 这些发现为改进电纤维的性能提供了一条途径,用于改进应用.
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