Synthetic Process Of 8-amino-2-methyquinoline And Its Application On The Preparation Of Yellow Pigment 138

Pigment Yellow 138 is one of the High Performance Pigments and is popularly used in coating, ink and plastic. Therefore, the thesis designed a new and simple process route to synthesize the pigment:at first, under the optimum reaction factors, 2-methyl-8-nitroquinoline was synthesized from 2-nitroaniline and crotonaldehyde. And then, 8-amino-2-methylquinoline was acquired through the reduction of 2-methyl-8-nitroquinoline. Finally, C.I. Pigment Yellow 138 was synthesized by condensing 8-aminoquinaldine with tetrachlorophthalic.The influencing factors, such as the type of catalyst, the concentration and type of acid, the reaction time and temperature as well as the feed ratio were comprehensively discussed during the synthesis of 8-nitro-2-methylquinoline catalyzed by lewis acid; Besides, the synthesis process of pigment yellow 138 was systematicly studied by optimizing the lewis acid catalyst, the feed ratio, the reaction time, the reaction temperature and the solvent. The optimum conditions for the synthesis of Pigment Yellow 138 was:8-amino-2-methylquinoline (1mol):tetrachlorophthalic anhydride (2.4mol),10mol% of zinc chloride catalyst,190℃, 10h, the yield was 95%.In order to tell the differences of the pigmentation, the paper adopted different conditioning methods, such as organic solvent treatment, grinding with the surfactant, acid extraction, alkatine treatment and polymer dispersers. Then the applied properties were studied systematically:the products have good dispersibility, bright coloring, high tinctorial strength, excellent fastness to solvent and covering capacity, migration fastness, weather fastness and ligth fastness and so on. The performance of the pigments have the same properties comparable to the sample of commercial pigment.