Membrane made of polymers or polymer mixtures for the separation of liquid or gaseous media

Membrane made of polymers or polymer mixtures for the separation of liquid or gaseous media, wherein the polymer or polymer blend is melted and mixed with a pore-forming gas, and wherein takes place from the molten, gasified polymer or polymer mixture, the formation of the membrane, whereby the membrane surface, which is the subject medium to be separated in the practice of the cutting process, is formed to Erzeugung- a turbulent flow at least in the region near the surface rough with a surface roughness of> 5 microns to 97 microns.