FLOW GAS PERMEAMETER FOR DETERMINATION OF THE TRANSPORT PARAMETERS OFGASES AND WATER VAPORS THROUGH FLAT POLYMERIC MEMBRANES

The apparatus for determination of transport parameters, viz. permeabi lity and diffusion coefficients of gases and water vapours through fla t polymeric membranes, was constructed. A new construction of a permea tion cell in the unit with an operating valve of sample gas makes poss ible to measure the time dependence of diffusion process more reliably and with higher accuracy. The sensitivity and rate of response of the rmal conductivity detectors were also increased by the new arrangement of electronic circuits. The connection of apparatus with a computer i ncreases the productivity and reliability of measurement and provides a fast evaluation of experimental data. The apparatus, based on the di fferential permeation method with the conductivity detection of the co mposition of gaseous mixture by thermistors, has been calibrated for C O2, O-2, N-2, and water vapours at 25 degrees C. The precision of dete rmination of permeability coefficients is about 12 % in average; the v alues of diffusion coefficients can be determined with accuracy better than 10 %.