负度变化驱动热塑性弹性体的快速恢复
Haiming Chen1, Zaizheng Sun1, Kai Lu1,2
1Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, China.
Advanced materials (Deerfield Beach, Fla.)
|December 18, 2023
概括
这项研究引入了一种新的热塑性聚氨 (TPU) 材料,该材料在长距离拉伸时具有更强的弹性. 它通过利用负变量效应实现了超过95%的弹性,超过了典型的合成材料.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
- 材料机械学 材料机械学
背景情况:
- 聚合物材料的弹性通常由弹性来解释,忽视了变化 (ΔH).
- 这种模型不充分地解释了长距离可拉伸热塑性聚氨 (TPU) 由于物理交叉连接网络动态而降低的弹性.
- 由于TPU弹性的不良降低,使其在长距离可拉伸场景中的应用受到限制.
研究的目的:
- 为了提高长距离可拉伸热塑性聚氨 (TPU) 的弹性.
- 调查负变化 (ΔH) 在改善TPU回收方面的作用.
- 为要求高的应用程序设计具有卓越弹性的TPU.
主要方法:
- 在TPU中使用应变诱导相位分离构建了一个可逆的中间接口.
- 引入负变化 (ΔH) 效应以改善材料回收.
- 分析了影响弹性的结构因素,包括软段对称性和硬段内容.
主要成果:
- 在新开发的双软细分TPU中,实现了超过95%的弹性效率.
- 证明了与生物材料相匹配的弹性,并且优于许多合成高性能TPU (通常<80%).
- 观察到一个显著的hysteresis循环比超过50%,表明显著的能量消耗和回收.
结论:
- 负 ΔH 效应,由应变诱导的相分离促进,显著改善长距离可拉伸TPU的弹性.
- 开发的TPU具有很高的弹性和歇斯底里,使其适用于人工带和缓冲带等应用.
- 了解细分对称性和内容等结构因素对于设计先进的弹性弹性体至关重要.
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