SORPTION OF WATER VAPOR BY CHITOSAN MEMBRANES

Abstract

The kinetic and equilibrium measurements of water vapor sorption were carried out on the four kinds of chitosan membranes. The sorption isotherms were all sigmoidal, though one of the membranes showed a sigmoidal one which was accounted for by the solution mechanism in the high pressure range. The amount of sorption depended on the preparation method of the membranes. The diffusion coefficient at a given vapor pressure widely varied from one to another, From these results, the cohesive state of molecular chains in the amorphous region was discussed.