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在冷编程过程中对形状记忆聚氨性能的研究 走向其应用
Maria Staszczak1, Leszek Urbański1, Mariana Cristea2
1Institute of Fundamental Technological Research, Polish Academy of Sciences, 02-106 Warsaw, Poland.
Polymers
|January 23, 2024
概括
本研究探讨了热塑性聚氨形状记忆聚合物 (PU-SMPs) 的冷编程,证明了其在玻璃过渡温度以下的有效性. 冷编程为热编程提供了一种可行的替代方案,可维护材料完整性并增强高级应用的形状恢复.
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
- 机械工程 机械工程
背景情况:
- 热敏形状记忆聚合物 (SMPs) 提供由温度变化触发的形状恢复.
- 传统的"热编程"涉及将SMP加热到其玻璃过渡温度 (T) 以上,重塑和冷却,这可能导致热降解和限制应用.
- 热编程的局限性包括温度梯度,热膨胀和减少形状恢复特性,阻碍在苛刻的领域使用.
研究的目的:
- 研究热塑性聚氨形状记忆聚合物 (PU-SMPs) 的冷编程方法.
- 使用冷编程评估PU-SMP的结构,机械和热力学性能.
- 为了确定在T以下的温度下编程的PU-SMP的形状固定性和形状恢复率.
主要方法:
- 热塑性聚氨形状记忆聚合物 (PU-SMP) 的全面实验调查.
- 使用"冷编程"方法,将SMP变形到其玻璃过渡温度 (T ≈ 65 °C) 以下.
- 进行结构,机械和热力学表征以评估功能性质.
主要成果:
- 在室温下冷编程产生了大约90%的形状固定率和93%的形状恢复率.
- 在45°C (T-20°C) 进行冷编程后,形状固定率约为97%,形状恢复率为90%.
- 与热编程 (98%的固定性,90%的回收) 相比,冷编程表现出具有竞争力的性能,特别是在较低的温度下,而不存在材料降解的风险.
结论:
- 冷编程对于具有相对较高玻璃过渡温度的PU-SMP来说是一种可行的和有效的方法.
- 这种方法通过避免高于T的加热来保持材料完整性,使其对敏感应用具有吸引力.
- 该研究证实了PU-SMPs在广泛的应变范围内具有良好的形状记忆和固定性质,适用于电子,航空航天和飞机结构.
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