分析不同类型的聚烯的拉伸爬行行为,使用简单的分数差异粘弹性模型
Yasuhiko Otsuki1, Kou Hashimoto2, Yutaka Kobayashi1
1Research Center for GREEN Materials and Advanced Processing, Yamagata University, Yonezawa 992-8510, Yamagata, Japan.
Polymers
|April 26, 2025
概括
本研究引入了分数计算模型来预测聚烯爬行,区分初级,二级和三级阶段. 该模型准确地捕捉了各种聚烯类型的爬行应变过渡和最低应变速率.
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:
- 变形是聚合物在持续负荷下性能的一个关键因素.
- 预测聚烯 (PPs) 从初级爬行到三级爬行的过渡对于材料设计和寿命至关重要.
- 现有的模型可能无法完全捕捉控制PP爬行行为的复杂粘弹性和损伤机制.
研究的目的:
- 开发和验证一个微分差粘弹性微积分模型,用于预测各种聚烯的初级到三级爬行.
- 分析不同PP配方中爬行行为的应力和温度依赖.
- 评估三级爬行过程中的损伤进展及其与材料性质的相关性.
主要方法:
- 利用分数差异粘弹性微积分来建模爬行变形.
- 应用于压力和温度依赖的分数微分顺序的经验公式.
- 模拟的三级爬行作为一个有损坏的粘性物体,结合了温度的Arrhenius定律和应力依赖的Eyring/WLF模型.
- 对各种PP,包括原始和回收类型的实验爬行数据验证了模型.
主要成果:
- 该模型成功地预测了所有测试的聚烯的爬行变种和最小变种率.
- 同聚合物PP在三级爬行过程中表现出有限的损伤 (指数0.17),而抗冲击PP显示出显著的损伤 (指数~0.5).
- 回收的PP显示了中间的爬行特性,与原始材料一致,并遵守了蒙克曼-格兰特法.
结论:
- 开发的分数微积分模型有效地预测了各种聚烯的爬行特性.
- 该模型提供了对不同PP类型的三级爬行控制的独特损害机制的洞察.
- 这些发现证实了蒙克曼 - 格兰特法在各种PP材料和爬行机制中适用.
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