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Updated: Jan 13, 2026

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Studying Large Amplitude Oscillatory Shear Response of Soft Materials
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在聚乙烯的膜间无形区域中,粘性变形的刚度
P-Y Ben Jar1, Na Tan1, Salman Obaidoon2
1Department of Mechanical Engineering, University of Alberta, Edmonton, AB T6G 1H9, Canada.
Polymers
|January 10, 2026
概括
这项研究模拟了在多次放松测试期间使用弹-仪表盘模型模拟聚合物的应力下降. 结果表明,短期分支准确地模拟了在峰值应力附近的应力放松,而不依赖于聚合物密度或短链分支含量.
科学领域:
- 聚合物物理 聚合物物理
- 材料科学 材料科学 材料科学
- 类风病学 类风病学 类风病学
背景情况:
- 了解聚合物粘性弹性对于材料设计至关重要.
- 多重放松 (MR) 测试提供了关于聚合物在压力下行为的见解.
- 弹-仪表盘模型通常用于表示粘弹性特性.
研究的目的:
- 在聚合物放松过程中模拟应力下降,使用弹-仪表盘模型.
- 研究短链分支 (SCB) 含量和质量密度对聚合物粘性弹性的影响.
- 探索模型参数与聚乙烯无形相变形阻力之间的关系.
主要方法:
- 采用了弹 - 仪表盘模型,具有明显的长期和短期的Maxwell分支.
- 在乙烯/1-赫森共聚合物和乙烯同聚合物上进行多重放松 (MR) 试验.
- 分析了放松阶段的应力下降,与SCB含量和质量密度等材料特性相关.
主要成果:
- 弹-仪表盘模型使用固定的短期分支参数准确地模拟了在峰值应力附近的应力下降.
- 短期麦克斯韦分支的刚度并不单调地取决于SCB含量或质量密度.
- 与长期分支不同,短期分支的刚性表现出复杂的行为,具有不同的聚合物微观结构.
结论:
- 结合MR测试和弹-冲模型,可以描述聚乙烯无形相不同区域的刚性.
- 需要进一步的研究才能充分验证该模型探测特定无形相位的能力.
- 该研究强调了SCB含量和密度对短期粘弹性反应的细微作用.
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