Synthesis Of 2- (4 - Aminophenyl) -5 - Aminobenzimidazole And Study On Its High Performance Polymers

This paper aims to obtain 2-(4-Aminophenyl)-1H-benzimidazol-5-amine by the new method, we get high purity 2,3,5,6-aminopyridine and 2,5-dihydroxy pairs acidby improving the process of preparation, exploring the three monomers’ copolymerization process.We purifythe material 2,4-dinitroaniline by benzene.Use 10% palladium carbon as catalyst, we obtainthe intermediate 1,2,4-aminophenyl hydrochloride by catalytic hydrogenation. Use aqueous hydrochloric acid as the solvent, stannous as the stabilizer, we purified the intermediate 1,2,4-aminophenyl hydrochloride.Use polyphosphoric acid as the solvent, the P2O5 as catalyst, weremoved hydrogen chloride of the 1,2,4-aminophenyl hydrochloride and purify ethanol. We get 2-(4-aminophenyl) 5-amino-benzimidazole by cyclization and purify it. After aromatization and hydrolysis, we prepare2,5-Dihydroxyterephthalic acid(DHTA). We obtain2,3,5,6-tetraaminopyri bynitration and hydrogenation.By de-HCl method, we obtain a polymer A-P by situ polymerization. And we spun out continuous fibers bydryspray-wet spinningprocess. And we studied its structure, performance.We characterize the structures of the nitrification intermediate and monomers by FT-IR, 1H-NMRand13C-NMR. HPLC result shows the purity of 2-(4-Aminophenyl)-1H-benzimidazol-5-amine is 99.35%, purificatedDHTAis 99.77%, and TAP?3HCl?H2O is 99.73%.We characterized the structure of A-P fiber by FTIR, Raman and XRD. The results of SEM and AFM show that theA-P fiber have smooth surface and their diameters are about 40-50μm.The tensile strength of the fiber is PIPD 1.99 Gpa by measuring, show that it has good mechanical properties. Within a temperature range of 30-800 ℃, nitrogen thermal gravimetric analysis results show that, A-P fiber has good thermal stability.