改进了对二次反应中的烯酸盐自由基聚合速率系数的初步计算方法
Fernando A Lugo1, Mariya Edeleva2, Paul H M Van Steenberge1
1Laboratory for Chemical Technology (LCT), Department of Materials, Textiles, and Chemical Engineering, Ghent University, Technologiepark-Zwijnaarde 125, 9052 Ghent, Belgium.
Polymers
|April 13, 2024
概括
预测聚合物结构是具有挑战性的,因为在激进聚合过程中发生的二次反应. 这项研究使用ab initio计算和动力蒙特卡洛模拟为这些反应提供了准确的动力学数据.
科学领域:
- 聚合物化学 聚合物化学
- 计算化学的计算化学
- 化学动力学 化学动力学
背景情况:
- 激素聚合中的二次反应使动力建模和聚合物结构预测复杂化.
- 对于动力学数据来说,这些反应的实验性隔离和测量具有挑战性.
- 准确的动力学数据对于精确的聚合物结构预测和反应工程至关重要.
研究的目的:
- 在烯酸根聚合过程中计算预测二次反应的内在速率系数的综合数据集.
- 开发和验证新的计算方法来预测复杂聚合反应的速率系数.
- 用动力蒙特卡洛模拟来比较初始预测与实验数据的准确性.
主要方法:
- 使用solvation校正的M06-2X/6-311+G (d,p) ab initio计算来确定速率系数.
- 开发了两种新的计算方法:明确的体会计和降低灵活性强加.
- 采用动力蒙特卡罗 (kMC) 模拟来对不同条件下的实验数据进行基准预测.
主要成果:
- 创建了一个完整和一致的数据集,用于关键次要反应的内在速率系数 (backbiting,β-scission等). ) 的情况.
- 当通过kMC模拟进行验证时,ab initio预测与实验数据有很好的一致性.
- 拟议的计算方法在弥合实验和计算化学差距方面表现出有希望.
结论:
- 这项研究成功地为二次激素聚合反应提供了准确的动力学数据.
- 新的计算策略增强了对复杂反应的速率系数的预测.
- 这项工作通过整合计算和实验发现,促进了改进的聚合物反应工程.
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