多氯联苯醚和多溴联苯醚理化性质的定量结构-性质关系研究

Quantitative structure-property relationship study on physicochemical properties of polychlorinated diphenyl ethers and polybrominated diphenyl ethers

多氯联苯醚(PCDEs)和多溴联苯醚(PBDEs)是分布广泛的污染物,有环境持久性和生物蓄积性。文中采用多元回归分析方法,以氯碎片常数为变量,建立了PCDE同类物水中溶解性、正辛醇/水分配系数、蒸汽压(293 K)等理化性质的线性关联式,也建立了PBDE同类物正辛醇/水分配系数、正辛醇/空气分配系数、蒸汽压(293 K)等理化性质的关联式。关联式对PCDEs和PBDEs的理化性质进行了估算,其结果与文献报道的实验值相当吻合。结果表明:采用PCDEs/PBDEs分子中氯/溴取代总数、氯/溴的邻位取代数目和相邻取代位置上均为氯/溴取代的成对数目作为变量,可以表述PCDEs/PBDEs的定量结构-性质关系。利用简单易得的描述符建立的QSPR模型是合理的、适用的。

Polychlorinated diphenyl ethers （PCDEs） and polybrominated diphenyl ethers （PBDEs） are among the widespread organic pollutants. They are persistent in the environment and accumulative in many species. Based on the multiple regression analysis the linear correlation equations of polychlorinated diphenyl ethers for aqueous solubility, n-oetanol/water partition coefficient, 293 K supercooled liquid vapor pressure were established by using chlorine fragment constants. The similar equations of polybrominated diphenyl ethers for n-octanol/water partition coefficient, n-octanoL/air partition coefficient, 293 K supercooled liquid vapor pressure were also established. The equations gave estimations in good agreement with the other experimental data of the physicochemical properties for PCDEs and PBDEs, and the validity of these equations was demonstrated. The results show that the total number of chlorines/bromines, the number of ortho-chlorine/bromine atoms and the number of pairs of adjacent chlorine/ bromine atoms can be used to express the quantitative structure-property relationship （QSPR）of PCDEs/PBDEs. The QSPR models which employ easily calculable molecular descriptors appear reasonable and useful.