一个自我愈合的系统,用于多环丁热
Young Bum Lee1,2,3, Benjamin A Suslick1,4, Derek de Jong1,3
1Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA.
Advanced materials (Deerfield Beach, Fla.)
|December 13, 2023
概括
这项研究引入了一种新型的微囊系统,用于自愈热聚合物,在高温前端聚合过程中保持稳定. 该系统有效地恢复机械性能,在polyDCPD材料中显示出90%以上的愈合效率.
科学领域:
- 聚合物科学与工程 聚合物科学与工程
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 自愈聚合物提高了材料的寿命和耐用性,但面临着制造方面的挑战,特别是对于需要高加工温度的热聚合物.
- 现有的自我修复系统往往与热加工条件不兼容,例如正面聚合 (FP).
研究的目的:
- 开发一种自愈的微囊系统,兼容于结构热的正面聚合 (FP).
- 创建一个热稳定的自我愈合系统,可以集成到热制造工艺中.
主要方法:
- 设计了一种由两部分组成的微囊系统,其中包含一个热潜伏的格拉布斯型催化剂和一个与二cyclopentadiene (DCPD) 单体的Cu (I) 同反应剂.
- 在FP条件下 (≈200°C) 评估了系统的稳定性和性能.
- 使用 Lap-shear 测试和 缩型双斜梁测试来评估接口强度和自我修复效率.
主要成果:
- 自愈系统在FP期间表现出热稳定性,催化剂由Cu (I) 同反应剂激活.
- 微囊系统使得DCPD在矩阵损伤时能够高效的聚合.
- 在坚固的polyDCPD热中,实现了超过90%的自我愈合效率,恢复了机械性能.
结论:
- 成功开发了一种与FP制造热相容的新型自我修复微囊系统.
- 该系统使用热潜伏的催化剂被辅助反应剂激活,使得多DCPD的有效治愈.
- 这种方法提供了一个可行的解决方案,用于将自我愈合能力纳入结构热材料.
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