Abstract
Permeation is a function of diffusion and solubility of the solvent/ polymer system. A physical-chemical constant that has been used previously to predict solubility is the three-dimensional solubility parameter (3-DSP). This paper reports a method for calculating the 3-DSP for the polymer Viton®, new permeation data for Viton and 14 solvents, and the application of the 3-DSP to a model for predicting permeation parameters. The 3-DSP values for Viton (J/cc)1/2 were dispersion=17.0, polar=10.6, and hydrogen bonding=6.1. A correlation coefficient of 0.65 was obtained when the natural log of breakthrough time for 19 solvents was regressed against the differences of the 3-DSP's for these 19 solvents and Viton. A value of 0.69 was obtained for the natural log of the permeation rate vs 16 solvent-Viton 3-DSP differences. While the variance unaccounted for in these regression tests does not allow quantitative prediction of permeation parameters, qualitative prediction of polymer suitability is possible.