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滑环交联弹性体的断裂性质的分子机制
Ruibin Ma1,2, Yang Zhang1,2, Xiangbao Wang1,2
1State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, 100029, People's Republic of China. gaoyy@mail.buct.edu.cn.
Nanoscale
|March 13, 2026
概括
滑动环交联弹性体 (SRCE) 具有增强的断裂性. 这项研究表明,中度的交叉连接最大化了断裂能量,而更高的SR覆盖率减少了它,澄清了SRCE中的分子断裂机制.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 计算建模 计算建模
背景情况:
- 滑动环 (SR) 交联弹性体 (SRCE) 以其高断裂性而闻名.
- 控制SRCE中骨折的精确分子机制尚不清楚.
- 了解这些机制对于设计先进的弹性体材料至关重要.
研究的目的:
- 用粗粒度模型研究SRCE中骨折的分子机制.
- 为了确定交叉连接密度和SR覆盖面对断裂能量和行为的影响.
- 阐明链动力学和键断裂在断裂过程中的作用.
主要方法:
- 为SRCE构建一个粗粒度模型,具有不同的交叉连接密度和SR覆盖范围.
- 模拟三轴变形以分析断裂特性.
- 对链形球性,SR分布,滑动距离和键断裂模式的分析.
- 虚空进化的量化,包括核形成,生长和凝聚.
主要成果:
- 在中等SR交叉连接密度下达到的最大断裂能量,明显超过非交叉连接材料.
- 断裂能量随着SR覆盖率的增加而减少.
- 链滑动和键断裂动态取决于应变,并受到交叉连接和SR覆盖的影响.
- 空隙核形成发生在低模量区域和断裂键处,在高交叉连接密度和低SR覆盖率下增长减少.
结论:
- 适度的SR交联优化了SRCE中的断裂能量.
- 增加的SR覆盖面通过改变链动态和键断裂,对断裂能量产生负面影响.
- 该研究提供了详细的分子层次了解SRCE断裂,确定了材料设计的关键参数.
- 高交叉连接密度和低SR覆盖率对抑制空洞演变和增强断裂抵抗有好处.
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