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幻象链模拟用于各种链密度的星聚合物网络的断裂
Yuichi Masubuchi1, Takato Ishida1, Yusuke Koide1
1Department of Materials Physics, Nagoya University, Nagoya 4649603, Japan. mas@mp.pse.nagoya-u.ac.jp.
Soft matter
|August 23, 2024
概括
这项研究表明,聚合物网络断裂特征取决于循环排名和预聚合物度. 机械性能,如应力和断裂工作,随着度的增加而增加,形成依赖于这个因素的主曲线.
科学领域:
- 聚合物科学与工程 聚合物科学与工程
- 材料科学 材料科学 材料科学
- 计算材料科学科学 计算材料科学
背景情况:
- 聚合物网络结构和断裂行为之间的关系仍然不太清楚.
- 以前的模拟显示,断裂特征与循环排名 (网络每个节点的闭环) 相对相关.
研究的目的:
- 为了研究预聚合物度 (c) 对聚合物网络断裂特征的影响.
- 通过对一系列重叠度 (c/c*) 的网络进行分析,扩展先前的发现.
主要方法:
- 模拟使用布朗动力学的星分支幻珠弹链.
- 多种分支臂 (f=1-8) 和转换比 (φc=0.6-0.95) 来创建聚合物网络.
- 进行单轴拉伸,最大限度地减少能量,以确定机械性能 (模块,断裂时的应变/应力,断裂工作).
主要成果:
- 与周期排名 (ξ) 相对绘制的断裂特征 (断裂时的应变) 形成了主曲线,与先前的工作一致.
- 模块,断裂时的应力和断裂工作也形成了主曲线,当通过分支点密度 (υbr) 进行正常化并与周期排名进行绘制时.
- 这些主曲线依赖于度 (c); 机械性能随着度的增加而单调地增加.
结论:
- 预聚合物度除了循环排名外,还显著影响聚合物网络断裂行为.
- 断裂特征不能仅仅通过网络的模量来预测.
- 这些发现提供了对聚合物网络机制和故障的更全面的理解.
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