摘要 |
<p>Composite membranes suitable for separating gas mixtures are made by in situ crosslinking of aminoorganofunctional polysiloxane, 1 to 9 mol percent aminosiloxane units, with diisocyanate on the surface of a highly porous polymer substrate, such as polysulfone. Using the crosslinked polysiloxane as a gutter layer, a gas separating entity can be coated on the gutter layer to make a double layer composite membrane which has a higher separation factor than the crosslinked polysiloxane and can be used effectively for flat sheet membranes, as well as, hollow fiber membranes.</p> |