耐裂和自我愈合的被动辐射冷却化合物
Cong Guo1, Chuanlong Li1, Zeshuang Qiao1
1College of Polymer Science and Engineering, National Key Laboratory of Advanced Polymer Materials, Sichuan University, Chengdu, 610065, China.
Advanced materials (Deerfield Beach, Fla.)
|February 28, 2025
概括
这项研究引入了一种自我愈合,抗裂纹的辐射冷却材料. 它自主修复裂,恢复冷却性能并提高户外应用的耐用性.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 热力学是一种热力学.
背景情况:
- 户外材料,特别是被动辐射冷却的材料,遭受裂损伤,损害阳光散射和热量排放.
- 太阳光吸收或通过裂传播会降低冷却系统的效率.
- 现有的材料缺乏强大的抗裂和自我修复能力,无法长时间在户外使用.
研究的目的:
- 开发一种具有自我愈合和抗裂特性的新/介电辐射冷却化合物.
- 在环境压力下提高被动辐射冷却系统的耐用性和功能.
- 为了研究动态键网络中自我修复和裂纹抵抗的机制.
主要方法:
- 一种聚合物的合成,具有UV-vs-NIR透明的键部分和化 (BN) 介电材料.
- 制造一个动态的聚合物/电介质键网络,将BN纳入太阳光散射器和键接受器.
- 裂愈合效率,断裂能量和冷却性能恢复的表征.
- 分析聚合物链流动性和键重组的自愈机制.
主要成果:
- 开发的化合物表现出自主自我修复的裂从微米到毫米宽.
- 自愈后,冷却性能恢复到大约100%左右.
- 由于刚性BN和牺牲性键的组合,裂纹能量增加了865%,防止了裂纹的传播.
- 这种材料在应力下表现出自主裂和曲折.
结论:
- 这种新/消电化合物为辐射冷却应用提供了卓越的自我愈合和抗裂性能.
- 动态键网络有效地恢复材料完整性和损坏后的冷却功能.
- 这种材料非常适合要求高,长期户外应用,需要强大的性能.
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