关于在9,10-二-9--10-酸-10-酸阻燃剂中的P-C键解离度的理论研究
Peilei Jiao1, Wenrui Zheng1, Jinglei Cui1
1College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, China.
The journal of physical chemistry. A
|July 22, 2024
概括
这项研究调查了9,10-二-9--10-酸-10-氧化物 (DOPO) 阻燃剂 (DOPO-FRs). 使用MN12-L密度函数理论计算的P-C键解离能量 (BDE) 与阻燃性相关,指导了新型高性能DOPO-FRs的设计.
科学领域:
- 材料科学 材料科学 材料科学
- 计算化学计算化学
- 聚合物化学 聚合物化学
背景情况:
- 9,10-二-9--10-烯-10-氧化物 (DOPO) 阻燃剂 (DOPO-FRs) 由于其效率和环境效益而越来越突出.
- P-C 键断裂是影响DOPO-FRs阻燃功效的关键因素.
- 需要准确的理论方法来预测和理解阻燃机制.
研究的目的:
- 评估不同密度函数理论 (DFT) 的准确性,用于计算DOPO-FRs中的P-C键解离能 (BDE).
- 调查P-C BDEs与各种DOPO-FR的阻燃性能之间的关系.
- 根据理论见解,设计具有增强阻燃性能的新型DOPO-FR.
主要方法:
- 对比DFT方法以确定P-C BDE计算中最准确的方法,确定MN12-L是优越的,其平方根平均误差最低 (1.85kcal/mol).
- 对于各种DOPO-FRs的P-C BDEs的理论计算,包括芬胺,[d]醇胺,醇胺和林衍生物.
- 计算BDE与实验性阻燃性数据 (LOI和UL-94测试) 之间的相关性分析.
主要成果:
- 计算P-C BDEs和实验性阻燃效应之间确立了强烈的相关性.
- 对于单个DOPO单元的有效阻燃碎片的排名: furan > thiophene > triazole > imidazole.
- 与丁三醇碎片的Bis-DOPO系统相比,与二甲基胺对应物相比,具有更高的阻燃性.
- 在有效碎片上存在两个电子捐赠组 (EDG),导致叠加的阻燃效应,提高性能.
结论:
- MN12-L DFT提供了准确的P-C BDE计算,这对于理解DOPO-FR机制至关重要.
- P-C BDE 作为预测阻燃性能的可靠描述符.
- 合理的DOPO-FR分子设计,考虑到碎片效应和替代物特性,可以显著提高阻燃性.
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