使用ReaxFF力场模拟聚烯和聚烯在冲击压缩和机械裂变下降解的模型
Tomasz Panczyk1, Krzysztof Nieszporek2, Pawel Wolski1
1Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences ul. Niezapominajek 8, 30239 Cracow, Poland.
Chemosphere
|April 19, 2024
概括
这项研究使用了反应分子动力学模拟来研究聚烯 (PP) 和聚烯 (PS) 的降解. ReaxFF-CHO力场准确地预测了材料属性,并揭示了在压力下明显的碎片化和交联行为.
科学领域:
- 材料科学 材料科学 材料科学
- 计算化学计算化学
- 聚合物科学 聚合物科学
背景情况:
- 聚烯 (PP) 和聚烯 (PS) 是广泛使用的聚合物.
- 了解它们的机械和化学降解对于材料设计和安全至关重要.
- 反应性分子动力学提供了一个强大的工具,以探测原子水平的降解机制.
研究的目的:
- 全面调查PP和PS的机械和化学降解.
- 为了验证ReaxFF-CHO力场对模拟聚合物降解的准确性.
- 阐明在各种机械刺激下发生的碎片化路径和化学反应.
主要方法:
- 使用ReaxFF-CHO力场进行反应分子动力学模拟.
- 均衡模拟用于密度和点的确定.
- 机械性质的非平衡模拟 (应力-应变,扬模量).
- 机械裂变和冲击压缩模拟以研究碎片化和反应途径.
主要成果:
- ReaxFF-CHO力场准确地复制了密度,相位过渡温度和PP和PS的Young模块等关键材料特性.
- 模拟显示了两种聚合物的骨干断裂,产生终端-CH2·和-CH·-基.
- 聚烯呈现出显著的碎片化,而聚钢则显示出交叉链接的倾向.
- 冲击压缩模拟确定了通过增加压力激活的化学反应.
结论:
- 使用ReaxFF-CHO力场的反应分子动力学是研究聚合物降解的可靠方法.
- PP和PS表现出不同的降解机制,分别涉及碎片化和交叉链接.
- 该研究提供了关于聚合物对机械应力和能量输入的反应的原子层次见解.
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