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在双分散纠聚合物的快速流动下,在剪切应力下对双峰的原始链网络模拟
1Department of Materials Physics, Nagoya University, Nagoya 464-8603, Japan.
Polymers
|June 19, 2024
概括
在聚合物混合物中,双峰切割应力现象是由短链方向和长链拉伸引起的. 模拟结果澄清了这些峰值在纠聚合物动态中的起源.
科学领域:
- 聚合物物理 聚合物物理
- 类风病学 类风病学 类风病学
- 计算材料科学科学 计算材料科学
背景情况:
- 纠的线性聚合物的双模混合物可以表现出复杂的剪切应力反应.
- 之前的实验报告了在特定的快速启动剪切变形下,剪切应力发展的双峰.
研究的目的:
- 阐明剪切应力发展中的双峰现象的分子起源.
- 分析不同聚合物链组件对观察到的应力行为的贡献.
主要方法:
- 基于原始链网络模型的多链滑链模拟.
- 对双模聚烯溶液的文献数据的分析.
- 剪切应力的分解成长链和短链贡献.
- 将压力解为段数,拉伸和方向.
主要成果:
- 模拟结果与实验数据有很好的一致性.
- 第一个应力峰值归因于短链的方向.
- 第二个应力峰值归因于长链拉伸.
- 峰值位置独立于连锁混合,但第二个峰值的强度复杂地取决于混合条件.
结论:
- 多链滑链模型成功地解释了双模聚合物混合物的双峰剪切应力现象.
- 了解链条动力学,特别是方向和拉伸,对于预测聚合物质行为至关重要.
- 混合条件显著影响来自不同链条长度的应力贡献的大小.
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