[Porous tarflen as a possible membrane material for blood membrane oxygenators. II. Diffusion properties]

Diffusion studies of tarflen porous barriers of home make and porous teflon membranes of American make as well as selected nonporous membranes, in an isobaric system: O2 - barrier - CO2 were performed in order to evaluate the effectiveness of O2 and CO2 exchange through the barriers listed above. O2 and CO2 diffusivities for porous barriers and O2 and CO2 permeability coefficients for nonporous membranes were determined. It was found that under isobaric conditions the diffusion rates of O2 and CO2 through the porous barriers are several orders of magnitude higher than that through the nonporous membranes, and that the surface areas of the porous barriers required for adequate O2 and CO2 exchange under oxygenator conditions are several orders of magnitude smaller than those of the nonporous membranes. Macroporous character as well as simple structure of tarflen materials were confirmed.