| 摘要 |
<p>Anisotropic fluid separation membranes having an integral discriminating layer are formed from blends of two types of polyimides. The first type is a phenylindane containing polyimide. The second type consists of polyimides formed from the reaction of benzophenone tetracarboxylic dianhydride (BTDA) and optionally pyromellitic dianhydride (PMDA), with toluene diisocyanate (TDI) and/or 4,4'-methylene-bis-phenylisocyanate (MDI). The ratio of Type 1 polymer to Type 2 polymer is 1 or less. The blend membranes are particularly useful for gas separation.</p> |
