Preparation of Polyimides Composed of Melamine and Benzophenone-3, 4: 3', 4'-bis(carboximide) Units

Abstract

2-Diphenylamino- or 2-dibenzylamino-4, 6-bis(p- or m-aminoanilino)-1, 3, 5-triazines reacted with benzophenone-3, 4: 3', 4'-tetracarboxylic dianhydride in N, N-dimethylacetarnide to form solutions of poly (amic acid)s of high molecular wight. These polymers were converted to polyimides by heating at 150°C under reduced pressure. These polyimides are soluble in pyridine, dioxane, epichlorohydrin, m-cresol, tetrahydrofuran, formic acid, sulfuric acid and aprotic polar solvents such as DMA, DIViF, DMSO and NMP. The polyimides with the dibenzylamino substituent are thermally stable to heating up to 360°C, whereas those with the diphenylamino substituent are stable up to 430°C.