化学构成对聚二烯动态的影响
Rohit Ghanta1, Craig Burkhart2, Patrycja Polińska3
1Department of Chemical and Biomolecular Engineering, University of Tennessee, Tennessee, Knoxville 37996, USA.
The Journal of chemical physics
|July 24, 2023
概括
这项研究使用全原子模拟揭示了 cis 和 trans 聚二烯 (PI) 融物中不同的动态行为. 在更高的模式下,Trans-PI显示出更快的动态,而cis-PI显示出更大的短期动态异质性.
科学领域:
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
- 计算化学计算化学
背景情况:
- 大多数聚二烯 (PI) 研究集中在1,4-cis含量上,忽视了1,4-trans PI同聚合物和共聚合物的独特动态.
- 有限的研究表明,跨-PI具有独特的动态行为,需要进一步调查.
研究的目的:
- 研究化学架构 (cis vs. trans) 对聚二烯融的动态的影响.
- 使用全原子模拟来比较cis-PI和trans-PI的热力学,形状,结构和动态特性.
主要方法:
- 用全原子分子动力学模拟来建模cis-PI,trans-PI及其共聚合物.
- 分析包括热力学,形状和结构性质,链动力学 (平均平方位移,Rouse分析),局部细分移动性 (C-H向量重定位),中间不连贯的散射函数和非高斯位移.
主要成果:
- 与trans-PI相比,Cis-PI在较低的Rouse模式下表现出更快的翻译和重定向动态.
- 在更高的Rouse模式和局部细分运动中,Trans-PI表现出更快的动态.
- 非高斯位移表明,在短时间内,cis-PI的动态异质性增加,而trans-PI显示持续的偏差.
结论:
- 聚二烯的微观结构 (cis 与 trans 含量) 显著影响其融化动态.
- 全原子模拟提供了对PI动态的基本见解,对于材料设计和优化至关重要.
- 观察到相对移动性的交叉,取决于温度和分离长度.
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