Synthesis And Dyeing Performance Of Heterocyclic-Dicyanoethyl Azo Disperse Dyes

Recently, a kind of heterocyclic-dicyanoethyl azo disperse dyes have been intensively researched to produce bright colour shade, high molar extinction coefficient and good to excellent washig fastness and light fastness on polyester fibers. In the thesis, the three dicyanoethyl aromatic amines were prepared as coupling components, four heterocyclic amines as diazo components, twelve kinds of heterocyclic-dicyanoethyl azo disperse dyes were synthesized by diazotization and coupling reaction, which all of them were not reported in literature. Moreover, they were both confirmed by elementary analysis, IR,1H NMR. The dyeing performance of the dyes were assessed on polyester fiber, acetylated fir powder and cyanoethylated fir powder. Including three main points as follows:1、The synthesis and characterization of the three dicyanoethyl aromatic aminesIn the present of anhydrous AlCl3as catalyst, N,N-2-cyanoethyl aniline, N,N-bis(2-cyanoethyl)-m-toluidine and N,N-bis(2-cyanoethyl)-m-chloro-aniline were prepared by the Michael addition reaction of aninline, m-toluidine, m-chloroaniline with acrylonitrile, the yields of the three dicyanoethyl aromatic amines were84.6%～88.4%, the purity of them were all over99%. The structures of the three dicyanoethyl aromatic amines were characterized by elemental analysis, IR,1H NMR and MS.2、The synthesis and characterization of the twelve heterocyclic-dicyanoethyl azo disperse dyesUsing the above three dicyanoethy aromatic amines as coupling components,2-amino-5,6-dichlorobenzothiazole,2-amino-6-nitrobenzothiazole,3-amino-5-nitro-[2,1]-benzisothiazole,2-amino-3,5-dinitrothiophene as diazo components, twelve heterocyclic-dicyanoethyl azo disperse dyes A1B1～A4B3were prepared via the diazo reaction and coupling reaction, the yields of dyes were68%～91%and the purity of the dyes were all over95%. The twelve heterocyclic-dicyanoethyl azo disperse dyes were also confirmed by elemental analysis, IR,1H NMR.3、The UV-visible absorption of twelve heterocyclic-dicyanoethyl azo disperse dyesThe maximum absorption of the prepared azo compounds disperse dyes were from412to599nm in acetone but when they were recorded in DMF, the maximum absorption were between417and621nm and the values of the logarithm of molar extinction coefficient are in the range of4.24-4.97. Furthermore, to the same diazo components, when the C1and CH3were introduced to the coupling components, the spectroscopic properties are similar; to the same components, when the withdrawing groups like NO2were introduced compared with C1atom in the diazo components, the obvious bathochrom of the maximum wavelength will occur.4、The dyeing performance of twelve heterocyclic-dicyanoethyl azo disperse dyesThe dyeing performance of the synthesized azo disperse dyes were evaluated on polyester fiber, acetylated fir powder and cyanoethylated fir powder. The colour shade of the dyes are yellow, orange, violet and blue on polyester fibers and the dyebath exhaustion percentage was ranged from86.8%to95.6%, furthermore, the washing fastness is4～5and the light fastness is6～7. Which was indicated that the dyes on fibers were found to show bright colour shade, higher percentage of dye exhaustion, good to excellent washing fastness and light fastness. Furthermore, the dyed modified fir powder were found to show the similar color shade, the dyebath exhaustion percentage and washing fastness as the dyed fibers. It reveals that the prepared azo disperse dyes can not be only applied to the polyester fiber, but acetylated fir powder and cyanoethylated fir powder.It concluded that anhydrous AlCl3is a optimal catalyst to the dicyanoethyl of aromatic amines; The prepared heterocyclic-dicyanoethyl azo compounds are found to show wide colour gamut and high intensity of absorption in acetone and DMF; they are also showed high exhaustion percentage, bright colour shades, good to excellent washing fastness and light fastness on polyester fibers, modified fir powder; The encouraging results may be promising for practical uses as diseperse dyes in industry.In the thesis, a kind of heterocyclic-dicyanoethyl azo disperse dyes are found to show bright colour shade, high intensity of absorption, good to excellent light fastness and washing fastness, which enrich the colour gamut of azo disperse dyes with dicyanoethyl of aromatic amines and expand the application of azo disperse in wood dyeing. Moreover, the encouraging results are important in theory and practical uses for developing the new kind disperse dyes and dyeing on modified wood.