Keywords: 
• organic contaminants /
• LDPE-air partition coefficients /
• theoretical linear solvation energy relationship (TLSER) /
• quantitative structure-property relationship (QSPR)

Abstract: The partition coefficients of organic contaminants between polymer and air (K_P) are significant for designing passive sampler devices. Most of the K_P values are usually obtained from experimental measurements, which are not readily available for most of the polar and non-polar neutral organic chemicals. Therefore, current work aimed to establish mathematical models for predicting K_P values with the physicochemical properties of chemicals of interest. To make further improvements in measuring K_PA values, current study focused to develop theoretical linear solvation energy relationship (TLSER) and the quantitative structure-property relationship (QSPR) models for predicting polymer-water partition coefficients. The results of stepwise multiple regression indicated that both models fits well with objectives, and had robustness and predictive capacity. These two models had similar statistical results of adjusted determination coefficients (R_adj²) of 0.927 and 0.956, cross-validation coefficients (Q_LOO²) of 0.915 and 0.946, and external validation coefficients (Q_ext²) of 0.913 and 0.960, respectively. Mechanism interpretation suggested that the main factors governing the partition process between LDPE and air were the molecular polarizability and hydrophobicity. Current findings provide an excellent tool for predicting acute K_PA values for most of the common hydrophobic organic compounds within the applicability domains.