高周期寿命的Poly-p-Phenylene Benzodioxole纤维的双卡路里冷却
Danyang Feng1, Yicheng Xiao1, Ge Wang1
1State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials, College of Chemistry, Nankai University, Tianjin, 300071, China.
Macromolecular rapid communications
|August 12, 2023
概括
研究人员使用聚乙二醇 (PBO) 纤维开发了新的固态冷却. 自卷PBO纤维实现了显著的冷却 (-3.7K) 与高周期寿命,提供了一个有前途的制冷材料.
科学领域:
- 材料科学 材料科学 材料科学
- 热力学是一种热力学.
- 固态物理 固态物理
背景情况:
- 开发高循环寿命的高效固态冷却技术至关重要.
- 聚乙烯二醇 (PBO) 是一种以优良的机械性能而闻名的高性能纤维.
研究的目的:
- 为了研究PBO纤维中的弹性热量和双热量冷却效应.
- 探索PBO纤维作为高循环寿命固态制冷的潜在材料.
主要方法:
- 拉伸和扭曲PBO纤维束以诱导弹性热量和扭热量效应.
- 利用X射线衍射观察扭曲过程中的结构变化.
- 用液晶染料涂层自卷PBO纤维,用于应变敏感的应用.
主要成果:
- 实现了 -0.4 K 的弹性热量冷却和 -1.3 K 的双热量冷却.
- 一种自卷PBO纤维的最大冷却值为-3.7K,应力为35%.
- 对于自卷PBO纤维,记录了20万个周期的特殊循环寿命.
- 在纤维扭曲过程中观察到X射线衍射峰值强度的可逆变化.
- 一个应变敏感的颜色变化应用成功演示.
结论:
- PBO纤维具有显著的弹性热量和双热量冷却性能.
- 自卷PBO纤维为高性能,持久的固态制冷提供了一个有希望的途径.
- 观察到的应变诱导现象为新的传感器应用提供了可能性.
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