机械热效应 低晶体热塑性聚氨纤维的表征
Jiongjiong Zhang1, Yilong Wu2, You Lv2
1Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China.
Polymers
|December 17, 2024
概括
这项研究引入了一种热塑性聚乙氨 (TPU) 纤维,用于高效,低强度的机械热量冷却. 这种对传统制冷的环保替代方案提供了显著的温度变化,减少了能源投入.
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.
- 可持续能源 可持续能源
背景情况:
- 机械热量冷却为传统蒸汽压缩制冷提供了一个零碳的替代方案.
- 现有的形状记忆合金 (SMA) 机械热量装置需要高的驱动力,而且成本昂贵.
- 热塑性聚乙烯 (TPU) 弹性体是一个潜在的低成本,低力替代品.
研究的目的:
- 为了研究低结晶TPU弹性体纤维的机械热量特性.
- 为了比较TPU纤维中的弹性热量和双热量效应.
- 阐明对观察到的机械热量效应负责的潜在机制.
主要方法:
- 制造TPU弹性体纤维.
- 开发一种用于弹性热量和双热量测量的多功能机械测试仪.
- 广角X射线散射 (WAXS) 分析用于研究材料结构变化.
主要成果:
- 与NiTi SMAs (6001200 MPa) 相比,TPU纤维在明显较低的应力 (1030 MPa) 时表现出机械热量效应.
- 达到了10.2K的最大双热量热温度变化,超过了78.9%的弹性热量效应 (5.7K).
- WAXS数据表明,压力诱导的无形链对齐,而不是结晶,是机械热量反应的主要驱动因素.
结论:
- 低晶体TPU弹性纤维显示出有希望的低力,高效的机械热量冷却能力.
- 这些发现突显了热塑性弹性体在开发可持续制冷技术方面的潜力.
- 无形链对齐被认为是这些材料有效的机械热量性能的关键机制.
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