Abstract: The disclosure relates to a method for improving the selectivity of a membrane, specifically of a membrane comprising a blend of i) a polysulfone, polyethersulfone or polyarylethersulfone and ii) polyvinylpyrrolidone, characterized in that the membrane is coated with polydopamine and heparin in a one-step or two-step reaction or by in situ modification with polydopamine followed by coating with heparin. The disclosure further relates to a process for producing such modified membranes having an improved selectivity, and to a filtration/diffusion device comprising the membrane which can be used, for example, in hemodialysis applications.

Abstract: The present invention relates to a method for preparing a polyurethane foam, in particular an aerogel, from at least one polyisocyanate and at least one optionally recycled polyol, and to the use thereof.