Abstract: The thermal pressure coefficients and densities of six plasticizers for dimthyl phthalate,diethyl malonate,triethyl phosphate,tributyl phosphate,dibutyl oxalate,dibutyl sebacate have been measured over the temperature range of 25-85℃.The augmented van der Waals model is used to correlate the experimental data.A method of predicting the internal pressure of the plasticizers is established,and the new solubility parameters for thirty plasticizers are obtained.