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通过计算手段建立化学直觉,了解C8-Per-/多甲基碳氧酸的物理化学特性

Jonathan P Antle¹, Michael A LaRock², Zackary Falls³

¹Department of Chemistry, University at Buffalo, the State University of New York (SUNY), Buffalo, New York 14260, United States.

ACS ES&T engineering

|June 11, 2024

概括

这项研究使用COSMO-RS理论预测了150种八碳多/ perfluoroalkyl carboxylic 酸 (C8-PFCAs) 的物理化学特性. 结果揭示了化,和和功能化如何影响这些属性,特别是当接近头组时.

科学领域:

环境化学环境化学
计算化学计算化学
物理化学物理化学

背景情况:

聚/ perfluoroalkyl carboxylic 酸 (PFCAs) 是广泛使用的工业化学品.
了解它们的环境命运和行为需要了解它们的物理化学性质.
关于各种C8-PFCAs的特性,特别是关于结构变化的数据有限.

研究的目的:

预测150种不同的八碳PFCA (C8-PFCA) 的关键物理化学性质.
研究化,和,化和分支等结构因素对这些属性的影响.
为了准确的预测,利用 COnductor-like Screening MOdel for Realistic Solvents (COSMO-RS) 理论来进行精确的预测.

主要方法:

应用COSMO-RS理论对150个C8-PFCA结构进行pKa,Kow和K_lipid-w模型和预测.
在C8-PFCA结构中,功能化,化,和,化和分支的系统变化.
对预测的分区系数进行分析,以确定结构与属性之间的关系.

主要成果:

预测的酸分离常数 (pKa),八醇-水分区系数 (Kow) 和DMPC脂质膜-水分区系数 (K_lipid-w) 对于150个C8-PFCAs.
确定了趋势,表明与碳酸基头组最接近的功能化显著影响物理化学性质.
量化了不同程度的化,和,化和分支对分区系数的影响.

结论:

COSMO-RS 是一个可行的工具,用于预测C8-PFCAs的物理化学性质.
结构性修改,特别是在头组附近,在确定C8-PFCAs的环境分区行为方面发挥着至关重要的作用.
这些发现为环境风险评估和设计更安全的化学替代品提供了有价值的数据.

关键词:

在COSMO-RS的基础上,酸分离常数是酸分离的常数.膜水的分区系数氧醇水分区系数通过/多醇基物质.

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