Abstract
The efforts for preparing functional organic thin membranes are now being continued extensively. A novel stage of the organic thin layers with good separation properties was initiated by the successful preparation of asymmetric membranes for reverse osmosis by Loeb and Sourirajan. In these membranes the thin layers with active properties for separation are formed with the supporting layers by the phase-separation mechanism. In continual efforts to develop novel and high speciality functions, very thin organic membranes, such as monolayers and bilayers, have been prepared and made functional. These processes and future problems are briefly reviwed.
