Asymmetric gas separation membranes having graded density skins and macrovoid-free morphology comprised of glassy, hydrophobic polymers are disclosed which are effective for separation gases with significante increases in permeation while maintaining equal or greater separation electivity. The membranes...http://www.google.fr/patents/US4880441?utm_source=gb-gplus-shareBrevet US4880441 - Asymmetric gas separation membranes having graded density skins
Asymmetric gas separation membranes having graded density skins
