POLYIMIDE MOLDING AND ITS PRODUCTION

摘要

PURPOSE:To obtain a colorless and transparent polyimide molding by molding an organic polar solvent solution of a specified polyimide precursor and imidizing the molding. CONSTITUTION:An organic polar solvent solution of a polyimide precursor of a logarithmic viscosity (as measured in N-methyl. 2-pyrrolidone in a concentration of 0.5 g/100ml) of 0.3-5.0 is obtained by dissolving 5-30wt.% polyamic acid based on at least one of repeating units of formulas I-IV (wherein X1 is formula V or -SO2-; X2 is any one of formulas VI-VIII; and X3 is formula IX or X) in an amide organic polar solvent of a b.p. <=170 deg.C (e.g. dimethylacetamide). A molding of a polyimide precursor, obtained by molding this solution, is through dehydration by slowly heating to 100-350 deg.C optionally in a vacuum or an inert gas atmosphere to imidize the polyamic acid into a polyimide molding based on at least one of repeating units of formulas XI-XIV.