| abstract |
An anisotropic membrane is provided having excellent mechanical properties combined with good permeation characteristics which comprises a vinyltriorganosilane polymer or copolymer consisting of a dense layer, of average thickness between 0.01 and 10 Mu , and a porous layer with open pores, of thickness up to 500 Mu in which the volume of the interstitial spaces in the porous layer represents 20 to 80 percent of the total volume of the membrane. |