| 摘要 |
PROBLEM TO BE SOLVED: To provide a production method of polyimide capable of producing polyimide without using a solvent, and capable of obtaining the polyimide in a pellet form or granular form.SOLUTION: A method produces polyimide by reacting a tetracarboxylic acid dianhydride and a diisocyanate compound in a compressible fluid. The compressible fluid combines a compressible fluid having a boiling point of -30°C or less and a compressible fluid having a boiling point from -30 to 20°C and a critical temperature of 160°C or lower. The compressible fluid having a boiling point of -30°C or lower is preferably carbon dioxide or nitrogen. The compressible fluid having a boiling point from -30 to 20°C and a critical temperature of 160°C or lower is preferably methyl ether.SELECTED DRAWING: Figure 1 |
