Polycarbonate membranes and production thereof

摘要

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.