WATER VAPOR PERMEABILITY THROUGH LAMINATED MEMBRANE COMPOSED OF HYDROPHILIC AND HYDROPHOBIC LAYERS

Abstract

The flux equations for positive and negative directions in one dimensional flux through laminated membrane are constructed taking into account the concentration dependences of diffusion coefficient and solubility coefficient of penetrant in respective component layer, and the flux ratio about the two directions is calculated. The calculation is carried out in accordance with the experimental permeation results of laminated membranes of various combinations of hydrophilic and hydrophobic layers. The flux ratio shows the maximum at a certain relative vapor pressure. The vapor pressure which shows the maximum of flux ratio is analysed by the sorption and permeation behaviors of the component single membranes.