通过结构性异构体固化剂的混合化,通过自我固的环氧树脂
Woong Kwon1, Jiyeon Cheon1, Hei Je Jeong2
1Department of Textile System Engineering, Kyungpook National University, Daegu 41566, Republic of Korea.
Polymers
|March 13, 2025
概括
这项研究开发了一种使用异构固化剂的高玻璃过渡温度 (Tg) 环氧树脂的自我硬化方法. 最佳的混合物显著提高了破裂性,而不损害热稳定性,为先进的复合材料提供了实用解决方案.
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
- 复合材料 复合材料 复合材料
背景情况:
- 高玻璃过渡温度 (Tg) 的环氧树脂对于航空航天复合材料至关重要.
- 传统的硬化方法往往会降低加工能力和热稳定性.
- 控制固化环氧网结构提供了一个潜在的自我硬化策略.
研究的目的:
- 通过控制网络结构来研究环氧树脂的简单自硬化方法.
- 为了增强四甘油4,4'-二氨基二甲 (TGDDM) 环氧树脂的折断性,而不会牺牲其它特性.
- 探索使用异构固化剂,即3,3'-和4,4'-二氨基二硫 (DDS),用于自硬化.
主要方法:
- TGDDM环氧树脂用不同比例的3,3'-DDS和4,4'-DDS混合物进行了固化 (7:3, 5:5, 3:7).
- 评估了固化环氧网的断裂性和玻璃过渡温度 (Tg).
- 分析了交叉连接密度和自由体积变化,以了解硬化机制.
主要成果:
- 3,3'-DDS与4,4'-DDS的最佳7:3比率产生了一种自我硬化的树脂.
- 与TGDDM/3,3'-DDS相比,断裂性增加了30%,与TGDDM/4,4'-DDS相比,增加了100%.
- 自硬化树脂的Tg在241266°C之间,保持了高的热性能.
- 提高性与增加交叉连接密度和减少自由体积有关.
结论:
- 混合异构固化剂是高Tg环氧树脂的有效自硬化策略.
- 这种方法可以提高断裂性,而不会损害热稳定性或可加工性.
- 该方法提供了一种实用和有效的途径,用于提高先进复合材料中环氧树脂的性能.
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