The Role of Surfaces in Gas Transport Through Polymer Membranes

This paper describes a procedure to measure the permeability P, diffusivity D, and rate of adsorption k(1), thus determining the solubility S and rate of desorption k(2) of He, N(2), O(2), CH(4), and CO(2) on a polydimethylsiloxane (PDMS) membrane. The described procedure is able to determine experimentally all the physical quantities that characterize the gas transport process through a thin rubber polymer membrane. The experiments were carried out at room temperature and at a transmembrane pressure of 1 atm. The results are in good agreement with the available data in the literature and offer an evaluation of k(1) and k(2).