The measurement of solute diffusion coefficient in polymers at infinite dilution

Solute diffusion in polymers is studied at infinite dilution of solute by inverse gas chromatography. The diffusion model proposed by Romdhane and Danner is applied in this study. and the thickness of polymer film in packed column is evaluated using the method proposed by Braun and Guillet. The diffusion coefficients at infinite dilution for CH2Cl2, CHCl3, C2H4Cl2 and CCl4 in polyethylene are determined. It shows that: 1) The smaller is the molecular volume of the solute, the larger is the diffusion coefficient. 2) The diffusion coefficient increases with temperature.