Polymer−Water Partition Coefficients of Hydrophobic Compounds for Passive Sampling: Application of Cosolvent Models for Validation

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• 作者：Foppe Smedes ; Rinze W. Geertsma ; Ton van der Zande ; Kees Booij
• 刊名：Environmental Science & Technology
• 出版年：2009
• 出版时间：September 15, 2009
• 年：2009
• 卷：43
• 期：18
• 页码：7047-7054
• 全文大小：241K
• 年卷期：v.43,no.18(September 15, 2009)
• ISSN：1520-5851

文摘

Polymer−water partition coefficients (K_pw) of hexachlorobenzene, 41 polychlorinated biphenyls (PCBs), and 26 polyaromatic hydrocarbons (PAHs) were determined for low-density polyethylene (LDPE) and five different silicone rubbers. Partition coefficients were determined in ultra pure water and in a range of methanol−water mixtures. Different cosolvent models for the effect of methanol concentration on the polymer-mixture partition coefficient (K_pm) were used to validate the K_pw in pure water. Linear regression of logK_pm against the mole fraction (x) methanol over range 0 < x < 0.3 yielded the best results. The obtained logK_pws were best described by a correlation with molecular weight, for PCBs in combination with the fraction of chlorine atoms in the meta and para positions (standard deviations of 0.08 log units). Correlations with logK_ow were less good (standard deviations of 0.21 log units), partly as a result of uncertainties in the logK_ow estimates that were used. Similar K_pws were found for different batches of silicone rubber from the same supplier. Differences in logK_pws for silicone rubbers obtained from different suppliers ranged from 0.16−0.58.