There is described an ethylene-vinyl alcohol copolymer membrane comprising at least a skin layer on its surface and a porous layer supporting the skin layer. The porous layer, when the membrane is observed in the dry state with an electron microscope, contains vacuoles or voids, which present a mono-...http://www.google.com.au/patents/US4269713?utm_source=gb-gplus-sharePatent US4269713 - Ethylene-vinyl alcohol copolymer membrane and a method for producing the same
