Polyamide hollow fiber filtration membrane having barrier layer

摘要

A filtration membrane is disclosed which has an ultrafiltration rate of between 200x10-4 and 500x10-4 ml/sec.xcm2xbar at 20 DEG C. and which is substantially impermeable to albumin of a molecular weight of about 44,000 or greater. A process for producing a filtration membrane is also disclosed in which a polymer solution is extruded with a center liquid under conditions such that the ratio of the volume of polymer solution to the volume of center liquid is within the range of from about 2:1 to about 4:1 to form a membrane extrudate.