| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a treating process permitting treatment of a polyimide at low temperatures and a membrane having high performance or stability as a membrane for separation of a gas or a vapor. <P>SOLUTION: The polyimide treating process has a process of exposing the polyimide to a compound selected from dendrimers, hyperbranch polymers and mixtures thereof. The compounds are first- to fourth-generation dendrimers formed by cross-linking of polyimides. The polyimide may be in the form of a membrane, and, after the treatment, the membrane is formed into e.g. a gas separation membrane, a filtration membrane, a micro-filtration membrane, an ultra-filtration membrane, a reverse osmosis membrane or a pervaporation membrane. The membrane is suitable for separation of e.g. H<SB>2</SB>/N<SB>2</SB>, H<SB>2</SB>/CO<SB>2</SB>, He/N<SB>2</SB>and CO<SB>2</SB>/CH<SB>4</SB>and separation of a gas from a mixture of hydrocarbons containing C2-C4 ones. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
