MULTILAYER POROUS MEMBRANE AND PROCESS OF MANUFACTURE

摘要

A multilayer porous membrane formed of an extrudable polymer is provided. The membrane is formed by co-extruding at least two compositions, each of which comprises a heated porogen and polymer while in contact with each other under conditions to minimize or prevent unstable interfacial flow between extruded layers. In a preferred embodiment, the two compositions are different such that the layers have a different average pore size.