微结构反应性聚氨薄膜在现场聚合和薄膜形成过程中的演变
Huimin Duan1,2,3,4, Shuli Li1, Jinbiao Zhao1
1Zhejiang Provincial Engineering Research Center for Green and Low-Carbon Dyeing & Finishing, Zhejiang Sci-Tech University, Hangzhou, 310018, P. R. China.
Macromolecular rapid communications
|July 5, 2024
概括
反应型聚氨薄膜 (RPUF) 提供了绿色生产的好处. 这项研究阐明了它们的现场膜形成机制,揭示了开发高性能RPUF产品至关重要的三个不同阶段.
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
背景情况:
- 反应型聚氨薄膜 (RPUF) 由于其环保,低能耗和无污染的生产而越来越突出,为传统的盐酸和水性聚氨提供了可持续的替代品.
- 尽管它们具有优势,但在无溶剂系统中对RPUFs的精确微观结构演变和现场膜形成机制的理解尚不完全,这阻碍了优化材料设计.
研究的目的:
- 阐明在无溶剂介质中的反应性聚氨薄膜 (RPUF) 的现场聚合和薄膜形成机制.
- 在分子和宏观层面上研究RPUF形成过程中的微观结构演变.
主要方法:
- 利用时间-温度等价原理研究在恒温 (25°C) 下的RPUF形成.
- 监测粘度变化以跟踪从液态到固态的过渡.
- 通过各种分析技术来表征分子量,结合,结晶性,凝含量和相位形态.
主要成果:
- 粘度分析表明,在薄膜形成过程中,从液体转化为凝,最后转化为固态.
- 多添加和薄膜形成过程被成功地分为三个不同的阶段: 1) 链延伸和微晶化, 2) 凝和脱微晶化, 3) 微相分离和薄膜形成.
- 详细的表征证实了这些阶段发生的微观结构变化.
结论:
- 这项研究提供了对现场薄膜形成机制和反应性聚氨薄膜 (RPUF) 中微观结构演变的全面了解.
- 这些发现为控制合成和开发基于RPUF的高性能材料提供了有价值的理论指导.
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