在室温附近的铁电聚合物中具有很大的电热效应
Bret Neese1, Baojin Chu, Sheng-Guo Lu
1Materials Research Institute, Pennsylvania State University, University Park, PA 16802, USA.
概括
研究人员探索了用于冷却的极性聚合物中的电热效应 (ECE). 他们在P ((VDF-TrFE) 和相关聚合物中发现了重要的ECE,证明了先进固态冷却技术的潜力.
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.
- 聚合物科学 聚合物科学
背景情况:
- 将电场应用于极性聚合物可以改变二极性排序,并可能通过变化实现冷却应用.
- 电热效应 (ECE) 是固态冷却的一个有前途的现象,由电场下的材料变化驱动.
研究的目的:
- 研究铁电聚合物,特别是P ((VDF-TrFE) 和相关共聚合物的电热效应.
- 用于冷却应用,量化这些材料可以实现的异热变化和亚热热温度变化.
主要方法:
- 利用麦克斯韦关系连接热电系数和电热效应.
- 实验测量了铁电聚乙烯化物-三乙烯) [P(VDF-TrFE) ]共聚合物的ECE.
- 研究了一种放松性铁电聚合物,P ((VDF-TrFE-chlorofluoroethylene),用于室温附近的ECE.
主要成果:
- 在70°C以上的P(VDF-TrFE中 (铁电-电过渡以上) 取得了很大的电热效应.
- 观察到异热变化超过55 J/kg·K,并观察到超过12°C的阳热温度变化.
- 在P ((VDF-TrFE-chlorofluoroethylene) 中在室温附近证明了可比的ECE.
结论:
- 像P(VDF-TrFE) 这样的铁电聚合物表现出显著的电热效应,适合冷却.
- 放松铁电聚合物为室温固态冷却应用提供了潜力.
- 该研究强调了基于聚合物的电热材料的可行性,以实现高效的热管理.
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