斯科特·布莱尔 热塑性聚氨的分数型粘弹性行为
Christian Pichler1, Stefan Oberparleiter1, Roman Lackner1
1Material Technology Innsbruck, University of Innsbruck, Technikerstraße 13, A-6020 Innsbruck, Austria.
Polymers
|September 28, 2023
概括
本研究描述了热塑性聚氨 (TPU) 在不同温度和水含量下的粘性弹性. 结果显示了不同的爬行行为,受键动态的影响,这表明斯科特·布莱尔和洛姆尼茨模型捕捉了物质反应.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物物理 聚合物物理
- 类风病学 类风病学 类风病学
背景情况:
- 热塑性聚氨 (TPU) 表现出复杂的粘弹性行为.
- 温度和水含量等环境因素显著影响聚合物特性.
- 了解这些影响对于预测各种应用中的TPU性能至关重要.
研究的目的:
- 用爬行测试来实验性地描述热塑性聚氨 (TPU) 的粘性弹性特性.
- 为了研究温度和物理吸收的水含量对TPU爬行行为的影响.
- 使用分数型模型建模观察到的粘弹性反应.
主要方法:
- 在受控温度 (15,25,35°C) 和拉伸应力水平 (0.3,0.5,0.7MPa) 的TPU样本上进行了变实验.
- 物理吸收的水含量通过将样品暴露在从0到80%的相对湿度水平中来控制.
- 数据分析涉及温度依赖性的Arrhenius图表和水含量效应的分数类型模型 (斯科特·布莱尔和洛姆尼茨).
主要成果:
- 爬行参数的温度依赖性被阿雷尼乌斯图形准确地描述.
- 观察并建模了两种不同的物质反应:低水/温度时的斯科特·布莱尔类行为,高水/温度时的斯科特·布莱尔-洛姆尼茨组合行为.
- 在特定的温度和湿度值时,发现了与键动态相关的行为转变.
结论:
- 斯科特·布莱尔元素有效地模拟了TPU中的短期,近乎瞬间的粘弹性行为.
- 洛姆尼茨元素捕获了与高温和含水量下键重组相关的二次粘弹性机制.
- 这些发现为TPU的粘性弹性提供了洞察力,这对于材料设计和应用预测至关重要.
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