| 摘要 |
PROBLEM TO BE SOLVED: To stably produce a gas separating membrane having high separating performance while preventing the deterioration of gas permeability by firing a film of a polyimidazopyrrolone polymer at a specified temp. in an inert atmosphere. SOLUTION: A film of a polyimidazopyrrolone polymer is fired at 410-1,500 deg.C, preferably 450-900 deg.C in an inert atmosphere. The pref. firing time is about 10-120min, especially about 10-60min. The polyimidazopyrrolone polymer is preferably produced by polycondensing tetramine and tetracarboxylic acid dianhydride as essential components in a proper solvent such as N,N- dimethylacetamide or N-methylpyrrolidone optionally in the presence of a reaction assistant such as acetic anhydride, thionyl chloride, trifluoroacetic anhydride or benzoic acid, isolating the resultant precursor of polyimidazopyrrolone and bringing it into ring closure by heating at about 200-400 deg.C. |
