含有基的碎片对形成膜的聚胺 - 胺基胺的结构和特性的影响
Svetlana V Kononova1, Galina K Lebedeva1, Galina N Gubanova1
1Institute of Macromolecular Compounds, Russian Academy of Science, Bolshoy pr. 31, Saint-Petersburg 199004, Russia.
Membranes
|August 25, 2023
概括
在聚胺 - 胺基膜中存在残留溶剂,可增强甲醇的运输. 移除这种溶剂显著降低了透性和选择性,突出了溶剂相互作用和键在膜性能中的关键作用.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 分离科学 分离科学
背景情况:
- 密集的无孔膜对于分离过程至关重要.
- 聚胺-胺基为膜应用提供可调节的特性.
- 了解溶剂对膜性能的影响对于优化至关重要.
研究的目的:
- 研究新型聚胺 - 胺基膜的结构特征和运输特性.
- 为了评估含基的修饰碎片对蒸发的影响.
- 为了确定残留溶剂 (N-甲基-2-pyrrolidone) 在膜性能上的作用.
主要方法:
- 通过多重凝结合成 (共) 聚胺 - 胺基的合成.
- 制造密集的无孔造膜.
- 进行蒸发实验以评估运输特性.
- 热处理和溶剂排离,以去除溶剂.
- 对结构变化和键的分析.
主要成果:
- 研究了膜性质的不同摩尔比例的二胺 (DADHyDPhM:DADPhM).
- 剩余的N-甲基-2-pyrrolidone充当了增塑剂,增强了极地液体的运输,特别是甲醇.
- 移除残留溶剂大大降低了透性和选择性.
- 脱水循环导致具有低透性的脆薄膜.
结论:
- 由分子内和分子间结影响的结构变化是膜性能的关键.
- 剩余溶剂在这些聚胺-胺基膜的蒸发行为中起着关键作用.
- 精心控制溶剂含量和聚合物结构是有效的膜设计的必要条件.
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