检查非异酸聚氨/多面寡合基基素混合水凝中的水聚合物相互作用
Izabela Łukaszewska1, Artur Bukowczan1, Konstantinos N Raftopoulos1
1Department of Chemistry and Technology of Polymers, Cracow University of Technology, ul. Warszawska 24, 31-155 Kraków, Poland.
Polymers
|January 11, 2024
概括
用POSS纳米颗粒修改的非异酸聚氨 (NIPU) 由于良好的分散性,保持了水的亲和力. 水的吸收降低了这些NIPU-POSS材料的玻璃过渡温度 (Tg).
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
- 物理化学 物理化学
背景情况:
- 非异酸聚氨 (NIPU) 为传统聚氨提供了更安全的替代品.
- 多面体寡合性西尔斯基素 (POSS) 纳米颗粒可以增强聚合物特性.
- 了解水聚合物相互作用对于材料在潮湿环境中的性能至关重要.
研究的目的:
- 为了研究octa(3-hydroxy-3-methylbutyldimethylsiloxy) POSS (8OHPOSS) 对NIPU网络吸水行为的影响.
- 分析吸水对NIPU-POSS材料热性质的影响,特别是玻璃化过渡温度 (Tg).
- 阐明水聚合物相互作用和键动态的基本机制.
主要方法:
- 在各种相对湿度下 (高达97%),进行了吸附实验.
- 均衡吸附等热体使用布鲁纳瓦和古根海姆-安德森-德布尔 (GAB) 模型进行了分析.
- 福利埃变换红外光谱法 (FTIR) 用于研究结变化.
- 使用差分扫描热量计 (DSC) 确定玻璃过渡温度 (Tg).
主要成果:
- 用8OHPOSS修改的NIPU网络展示了布鲁纳uer III型吸异热体.
- 尽管POSS具有疏水性,但加入8OHPOSS并没有降低NIPU的水亲和力.
- FTIR分析表明,在吸水时,聚合物-聚合物键断裂,水-聚合物键形成.
- 在所有含水量增加的NIPU-POSS材料中,观察到Tg的显著下降,这归因于塑化和奴役效应.
结论:
- 在NIPU矩阵中8OHPOSS的均分散促进了水-聚合物相互作用.
- 水的吸收显著塑化了NIPU网络,导致降低了Tg.
- 在高水分水平下,POSS部分可能间接影响水吸收和塑化机制.
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