POLYSULFONE MEMBRANES .3. PERFORMANCE EVALUATION OF POLYETHERSULFONE PVP MEMBRANES

The performance of membranes produced from casting solutions consistin g of polyethersulfone (PES), poly-(N-vinyl-pyrrolidone) (PVP), and N-m ethyl-2-pyrrolidinone (NMP) were systematically studied. Zero-shear ca sting solution viscosities for these polymer solutions were determined as a function of PES and PVP concentrations. Ultrafiltration membrane s were then cast using the phase inversion technique and characterized by separation experiments using polyethylene glycols of various molec ular weights as test solutes. A pore flow model was fitted to the resu lting separation data to provide estimates of the average pore radius and membrane porosity. These parameters were used to compare laborator y results for this membrane casting solution system with performance d ata for commercially available polyethersulfone membranes,