循环碳酸盐和甘乙烯的异步环开放诱导了朝着无热和快速粘合的高级环氧粘合剂的相位演变
Peixin Niu1, Chuanlong Li2, Jun Zhu3
1College of Chemistry and Pingyuan Laboratory, Zhengzhou Key Laboratory of Elastic Sealing Materials, Zhengzhou University, Zhengzhou, 450001, China.
Angewandte Chemie (International ed. in English)
|June 27, 2024
概括
一种基于环氧基的新型结构粘合剂在室温下迅速固化,实现超粘合. 这种高性能材料为苛刻的工业应用提供快速粘合和特殊强度.
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
背景情况:
- 在汽车和电子行业对室温可固化的结构粘合剂的高需求.
- 开发具有快速,高粘合力的粘合剂在周围环境温度附近的挑战.
研究的目的:
- 设计一个室温可固化,快速粘合,超强的环氧基结构粘合剂.
- 研究用于增强粘合性能的跨尺度结构设计原则.
主要方法:
- 使用高分支拓的碳酸糖覆盖聚氨 (PUGC).
- 在环氧和PUGC之间设计异步交叉连接,以实现协同相位分离.
- 集成的动态键和弹性体域用于能量消散.
主要成果:
- 在4小时内达到16MPa的快速粘合强度增长,在7小时后达到21MPa.
- 与商业室温可固化环氧粘合剂相比,其表现显著优越.
- 设计的结构促进了快速交叉连接和高效的硬化.
结论:
- 开发的环氧基粘合剂表现出优异的室温固化,快速粘合和超强粘合.
- 跨度结构设计,包括PUGC拓和异步交叉连接,是高性能的关键.
- 这项工作推进了高性能粘合剂技术和室温固化策略.
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