计算机研究激素介导的硫醇环氧反应
Belma Gjergjizi Nallbani1, Memet Vezir Kahraman1, Isa Degirmenci2
1Chemistry Department, Faculty of Science, Marmara University, 34722 Istanbul, Turkey.
The journal of physical chemistry. A
|September 22, 2023
概括
硫醇和环氧化物之间的激素介导反应在添加方面缓慢,但在链转移方面快速. 这解释了固化系统的重叠,表明温度和醇的选择可以防止它.
科学领域:
- 聚合物化学 聚合物化学
- 计算化学计算化学
背景情况:
- 硫和硫环氧系统广泛用于工业应用.
- 了解反应机制对于优化固化过程和防止系统重叠至关重要.
研究的目的:
- 用计算方法阐明基因介导的硫醇环氧反应.
- 分析双固化系统 (乙烯/乙烯) 中的重叠问题.
- 为基因介导的硫醇环氧化物反应提出反应机制.
主要方法:
- 密度函数理论 (DFT) 的计算.
- 对九个环氧模型分子的评估.
- 在1.0 atm和298.15 K的模型反应机制使用M06-2X/6-31+G(d,p).
主要成果:
- 对于醇-环氧化物反应,已提出一种醇-乙烯类似机制.
- 环氧添加反应是缓慢的 (速率常数<10−4 M−1 s−1).
- 连锁转移反应是快速的 (速率常数>101 M-1 s-1),导致固化系统重叠.
- 关键的驱动力包括基稳定性,环氧环应变和基不稳定性.
结论:
- 在醇-环氧反应中的快速链转移有助于固化阶段重叠.
- 建议控制反应温度和仔细选择硫醇,以管理固化重叠.
- 计算洞察力为优化双固化系统提供了基础.
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