Production of asymmetric track membranes with a high permeability and separation selectivity

An investigation of the structure and surface properties of poly(ethylene) terephthalate track membranes (PET TM) with a changed pore profile subjected to the plasma RF-discharge is performed. It was arranged that effect of the non-polymerizing gas plasma on the membranes of researched sample leads to formation of asymmetric membranes possessing a higher flow rate. Choice of optimal discharge parameters allows one to etch the membrane in its layer. In this case in the membrane layer not affected by plasma, the mean pore diameter remains at its initial level. Preserving the initial (nominal) pore diameter allows one to perform the filtration processes with no decrease of separation selectivity. It is shown that the introducing of the polymerizing gas, cyclohexane, into the composition of plasma-forming gas provides improved hydrodynamic properties of asymmetric membranes.