优化单元环氧树脂的固化配置,使用含有可逆尿素键的小分子热隐性固化剂
S M Ashik Abedin1,2, Bekir Dizman1,2
1Integrated Manufacturing Technologies Research and Application Center & Composite Technologies Center of Excellence, Sabanci University, Istanbul, 34956, Turkey.
Macromolecular rapid communications
|May 12, 2025
概括
研究人员开发了新型热隐性固化剂 (TLCs),用于单元环氧树脂 (OCERs) 的可逆尿素键. 最有效的TLC,TLC-5,在120°C时实现了环氧固化,产生了Tg为135°C的材料.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
背景情况:
- 一组件环氧树脂 (OCER) 需要潜伏固化剂以控制反应性.
- 具有可逆尿素键的热隐性固化剂 (TLC) 提供了可调节的固化行为的潜力.
研究的目的:
- 合成和描述含有可逆尿素键的小分子TLC.
- 为了评估这些TLCs在基于Diglycidyl乙醇 bisphenol A (DGEBA) 的OCERs中的有效性.
- 研究分子结构对TLC稳定性和性能的影响.
主要方法:
- 通过芳香单异酸盐与酸氨酸的反应合成TLCs.
- 使用NMR,FTIR,TGA和DSC进行表征.
- 用DGEBA和TLCs制定OCER,然后进行治疗动力学分析 (DSC,风病学) 和材料性质评估 (DMA).
主要成果:
- 在DGEBA树脂中观察到TLC的均分散.
- TLC的稳定性和有效性受到基替代和氨基类型的影响.
- 来自二二异酸盐 (DCPI) 和三乙烯胺 (TETA) 的TLC-5显示出最佳性能,在120°C时启动DGEBA治愈.
- 在140°C固化后的OCER-5呈现出135°C的玻璃过渡温度 (Tg).
结论:
- TLCs的分子设计对于优化稳定性和固化效率至关重要.
- 开发的TLC显示了先进复合材料和粘合剂应用的前景.
- 这项工作为设计用于环氧系统的下一代隐性固化剂提供了基础.
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