Abstract: Membranes for hemodialysis prepared from polycarbonate materials have superior transport properties for middle molecular weight molecules than do cellulosic membranes while maintaining approximately the same ultrafiltration rate as cellulosic membranes. A percentage of patients treated using dialysers containing polycarbonate membranes show improved hematocrit and neurobehavioral functions.

Abstract: Polycarbonate membranes useful for hemodialysis are fabricated from polyether-polycarbonate block copolymers by a water gelation process. The process comprises casting onto a substrate surface a layer of a multicomponent casting solution comprising the copolymer dissolved in a water-miscible organic solvent together with a cosolvent which acts as a swelling agent for the copolymer, drying the layer to partially evaporate the solvents therefrom, immersing the partially dried layer in water to form a gelled membrane, and stripping the gelled membrane from the substrate surface. The membrane has improved strength and improved permeability to solutes in the "middle molecule" range while maintaing clinically acceptable ultrafiltration rates and clearance of low molecular weight solutes.

Abstract: Polycarbonate membranes useful for hemodialysis are fabricated from polyether-polycarbonate block copolymers by a water gelation process. The process comprises casting onto a substrate surface a layer of a multicomponent casting solution comprising the copolymer dissolved in a water-miscible organic solvent together with a cosolvent which acts as a swelling agent for the copolymer, drying the layer to partially evaporate the solvents therefrom, immersing the partially dried layer in water to form a gelled membrane, and stripping the gelled membrane from the substrate surface. The membrane has improved strength and improved permeability to solutes in the "middle molecule" range while maintaining clinically acceptable ultrafiltration rates and clearance of low molecular weight solutes.

Abstract: Thin membranes for hemodialysis prepared from polycarbonate materials have superior transport properties for middle molecular weight molecules than do cellulosic membranes or previously available thicker polycarbonate membranes while having an ultrafiltration rate less than that obtainable with thicker polycarbonate membranes. Thin polycarbonate membranes with a thickness of about 0.8 mil, an ultrafiltration rate of about 3.5 ml/hr/M.sup.2 /mmHg, a sodium chloride diffusive permeability of about 830 cm/min(.times.10.sup.-4) at 37.degree. C and a vitamin B.sub.12 diffusive permeability of about 114 cm/min .times. 10.sup.-4 at 37.degree. C have been produced.

Abstract: Polycarbonate membranes useful for hemodialysis are fabricated from polyether-polycarbonate block copolymers by a water gelation process. The process comprises casting onto a substrate surface a layer of a multicomponent casting solution comprising the copolymer dissolved in a water-miscible organic solvent together with a cosolvent which acts as a swelling agent for the copolymer, drying the layer to partially evaporate the solvents therefrom, immersing the partially dried layer in water to form a gelled membrane, and stripping the gelled membrane from the substrate surface. The membrane has improved strength and improved permeability to solutes in the "middle molecule" range while maintaining clinically acceptable ultrafiltration rates and clearance of low molecular weight solutes.